BRL 1961, BIBLIOGRAPHY, start page 1085

CHAPTER IV
BIBLIOGRAPHY

BRL 1961, BIBLIOGRAPHY, start page 1086

BIBLIOGRAPHY

Bell, Wm. D. "A Management Guide to Electronic Computers", McGraw-Hill, 1957.
Berkeley, E. C. "Computers: Their Operation & Applications", Reinhold, 1956.
Berkeley, E. C. "Giant Brains". John Wiley, 1949.
Caldwell, Samuel H. "Switching Circuits & Logical Design", John Wiley, 1958.
Canning, Richard G. "Installing Electronic Data Processing Systems", John Wiley, 1957.
Canning, Richard G. "Electronic Data Processing for Business & Industry", John Wiley, 1956.
Casey, R. S. and Perry, J. W. "Punched Cards", Reinhold, Copyright 1951, Second printing 1952.
Chapin, Ned "An Introduction to Automatic Computers". Van Nostrand, 1957.
Charnes, A., Cooper, W. W., Henderson, A., et. al. "Introduction to Linear Programming", Wiley, 1953.
Culbertson, James T. "Mathematics & Logic for Digital Computers", Van Nostrand, Copyright 1958.
Doss, Milburn P. "Information Processing Equipment". Reinhold, 1955.
Dwyer, P. A. "Linear Computations", Wiley, 1951.
Eckert, W. J. and Jones, R. "Faster, Faster', McGraw-Hill, 1955.
Gottlieb, C. C. and Hume, J. N. P. "High-Speed Data Processing", McGraw-Hill, 1958.
Grabbe, E. M., Ramo, S. and Wooldridge, D. E., (Editors) "Handbook of Automation, Computation and Control", Vol I: Control Funda- mentals; Vol II: Computers & Data Processing; Vol III: Systems & Components, Wiley, 1959.
Gregory, R. H. and Van Horn, R. L. "Automatic Data Processing Systems". Wadsworth Pub. Co., 1960.
Harvard University, staff of computation Lab. "Synthesis of Electronic Computing & Control Circuits", Harvard University Press, 1951.
Harvard University, Staff of Computation Lab. "Description of a Magnetic Drum Calculator", Harvard University Press, 1952.
Householder, Alston S. "Principles of Numerical Analysis", McGraw-Hill, 1953.
Keister, Wm., Ritchie, A. E., Washburn, S. H., et. al. "Design of Switching Circuits", Van Nostrand.
Korn, G. A. and T. M. "Electronic Analog Computers", McGraw-Hill, 1956.
Kozmetsky, G. and Kircher, P. "Electronic Computers & Management Control", McGraw-Hill, 1956.
Lewis, I. A. D. and Wells, F. H. "Millimicrosecond Pulse Techniques", Pergamon, 1955. 1086

BRL 1961, BIBLIOGRAPHY, start page 1087

BIBLIOGRAPHY (CONTINUED)
McCracken, D. D. "Digital Computer Programming", Wiley, 1957.
Millman, Jacob & Taub, H. "Pulse & Digital Circuits", McGraw-Hill, 1956.
Montgomerie, G. A. "Digital Calculating Machines & Their Application to Scientific & Engineering Work". Van Nostrand, 1957.
Murphy, John S. "Basics of Digital Computers", John F. Rider, copyright 1958.
Ore, Oystein "Number Theory & Its History", McGraw-Hill, 1948.
Phister, M., Jr. "Logical Design of Digital Computers", Wiley, 1958.
Pressman, Abraham I. "Design of Transistorized Circuits for Digital Computers", John F. Rider, 1959.
Richards, R. K. "Arithmetic Operations in Digital Computers", Van Nostrand, 1955.
Richards, R. K. "Digital Computer Components & Circuits", Van Nostrand, 1957.
Scott, N. R. "Analog & Digital Computer Technology", McGraw-Hill, 1960.
Smith, Charles V. L. "Electronic Digital Computers", McGraw-Hill, Copyright 1959.
Soroka, W. W. "Analog Methods in Computation & Simulation", McGraw-Hill, 1954.
Stewart, W. Earl "Magnetic Recording Techniques", McGraw-Hill, Copyright 1958.
Stibitz, Geo. R. and larrivee, Jules A. "Mathematics & Computers", McGraw-Hill, 1957.
Svoboda, Antonin "Computing Mechanisms & Linkages", McGraw-Hill, 1948.
Tompkins, C. B., Wakelin, J. H. and Stifler, W. W., Engineering Res. Associates "High Speed Computing Devices", McGraw-Hill, 1950.
Wass, C. A. A. "Introduction to Electronic Analogue Computers", Pergamon, 1955.
Wilkes, Maurice V. "Automatic Digital Computers", Wiley, 1956.
Weik, Martin H. "A Survey of Domestic Electronic Digital Computing Systems", Ballistic Research Laboratories Report No. 971, Reprinted by United States Department of Commerce Office of Technical Services, PB111996.
Weik, Martin H. A Second Survey of Domestic Electronic Digital Computing Systems", Ballistic Research Laboratories Report No. 1010, Reprinted by United States Department of Commerce Office of Technical Services, 111996 R.
Automatic Data Processing Systems: Department of the Army Regulations and Pamphlets
- Acquisition and use for business type operations: policies, procedures, etc. - AR 1-250
- Catalog of commercially available DA Pam 1-250-4
- Conducting studies DA Pam 1-250-1
- Industrial, scientific, and office types, Logistics responsibilities - AR 701-7440
- Introduction - DA Pam 1-250-3
- Program planning guide DA Pam 1-250-2

BRL 1961, BIBLIOGRAPHY, start page 1088

GoTo Table of Contents

BRL 1961, GLOSSARY, start page 1085

CHAPTER V
GLOSSARY OF COMPUTER ENGINEERING AND PROGRAMMING TERMONOLOGY
(REVISED)

BRL 1961, GLOSSARY, start page 1090

AC
a suffix meaning "automatic computer" as in ORDVAC, EDVAC, ENIAC, etc.
ACCESS, RANDOM
access to storage under conditions in which the next position from which information is to be obtained is in no way dependent on the previous one.
ACCESS TIME
(1) the time interval between the instant at which information is: (a) called for from storage and the instant at which delivery is completes, i.e., the read time; or (b) ready for storage and the instant at which storage is completed, i.e., the write time. (2) the latency plus the word-time.
ACCUMULATOR
the "zero-access" register (and associated equipment) in the arithmetic unit in which are formed sums and other arithmetical and logical results; a unit in a digital computer where numbers are totaled, i.e., accumulated. Often the accumulator stores one operand and upon receipt of any second operand, it forms and stores the sum of the first and second operands.
ACCURACY
freedom from error. Accuracy contrasts with precision; e.g., a four-place table, correctly computed, is accurate; a six-place table containing an error is more precise, but not accurate.
ADDER
a device capable of forming the sum of two or more quantities.
ADDRESS
a label such as an integer or other set of characters which identifies a register, location of device in which information is stored.
ADDRESS, ABSOLUTE
the label(s) assigned by the machine designer to a particular storage location; specific address.
ADDRESS, RELATIVE
a label used to identify a word in a routine or subroutine with respect to its position in that routine or subroutine. Relative addresses are translated into absolute addresses by the addition of some specific "reference" address, usually that at which the first word of the routine is stored, e.g. if a relative address instruction specifies an address n and the address of the first word of the routine is k, then the absolute address is n + k.
ADDRESS, SYMBOLIC
a label chosen to identify a particular word, function or other information in a routine, independent of the location of the information within the routine; floating address.
ALLOCATE
to assign storage locations to the main routines and subroutines, thereby fixing the absolute values of any symbolic addresses. In some cases allocation may require segmentation.
AMPLIFIER, BUFFER
an amplifier used to isolate the output of any device, e.g. oscillator, from the effects produced by changes in voltage or loading in subsequent circuits.
AMPLIFIER, TORQUE
a device which produces an output turning moment in proportion to the input moment, wherein the output moment and associated power is supplied by the device, and the device requires an input moment and power smaller than the output moment and power.
ANALOG
the representation of numerical quantities by means of physical variables, e.g. translation, rotation, voltage, resistance; contrasted with "digital".
ANALYZER, DIFFERENTIAL
an analog computer designed and used primarily for solving many types of differential equations.
AND-OPERATOR
a logical operator which has the property such that if P and Q are two statements, then the statement "P and Q" is true or false precisely according to the following table of possible combinations:
```
         P             Q           P and Q
       false    0    false     0    false     0
       false    0    true      1    false     0
       true     1    false     0    false     0
       true     1    true      1    true      1
   
```
The "and" operator is often represented by a center- ed dot (.), or by no sign, as in P ù Q or PQ; the term conjunction is applied to this 'operator.
AND-GATE
a signal circuit with two or more input wires which has the property that the output wire gives a signal if and only if all input wires receive coincident signals.
AQUADAG
a graphite coating an the inside of certain cathode ray tubes for collecting secondary electrons emitted by the screen.
ARITHMETIC UNIT
that portion of the "hardware" of an automatic computer in which arithmetic and logical operations are performed.
ASSEMBLE
to integrate subroutines (supplied, selected, or generated) into the main routine, by adapting, or specializing to the task at hand by means of preset parameters, by adapting, or changing relative and symbolic addresses to absolute form, or incorporating, or placing in storage.

BRL 1961, GLOSSARY, start page 1091

ATTENUATE
to obtain a fractional part or reduce in amplitude an action or signal. Measurement may be made as percentage, per unit, or in decibels, which is 10 times log 10 of power ratio; contrasted with amplify.
AUTOMATION
the entire field of investigation, design, development, application and methods of rendering or making processes or machines self-acting or selfmoving; rendering automatic; theory, art of technique of making a device, machine, process or procedure more fully automatic; the implementation of a self-acting or self-moving, hence, automatic process or machine.
AVAILABLE-TIME, MACHINE
time during which a computer has the power turned on, is not under maintenance, and is known or believed to be operating correctly.
AZIMUTH
the angular measurement in an horizontal plane and in a clockwise direction from a specific reference direction, usually a form of North, i.e., true azimuth is measured from true north, magnetic azimuth from magnetic north, grid-azimuth from grid north or thrust or base line. HAND a group of recording tracks on a magnetic drum.
BASE
a number base; a quantity used implicitly to define some system of representing numbers by positional notation; radix.
BEAM, HOLDING
a diffused beam of electrons used for regenerating the charges stored on the screen of a cathode ray storage tube.
BIAS
the average D.C. voltage maintained between the cathode and control grid of a vacuum tube; a fixed reference located with respect to a neutral or zero reference.
BINARY
a characteristic or property involving a selection, choice or condition in which there are but two possible alternatives.
BINARY, NUMBER
a single digit or group of characters or symbols representing the total, aggregate or amount of units utilizing the base two; usually using only the digits "0" and "1" to express quantity.
BIQUINARY
a form of notation utilizing a mixed base; see Notation, Biquinary.
BIT a contraction of binary digit; see Digit, Binary.
BLOCK
a group of words considered or transported as a unit; an item; a message; in flow charts, an assembly of boxes, each box representing a logical unit of programming, usually requiring transfer to and from the high speed storage; in circuitry, a group of electrical circuits performing a specific function, as in a "block" diagram, in which a unit, e.g., an oscillator, is represented as a geometric figure (symbol).
BLOCK, INPUT
a section of internal storage of a computer reserved for the receiving and processing of input information; input buffer.
BOOTSTRAP
the special coded instructions at the beginning of an input tape, together with one or two instructions inserted by switches or buttons into the computer; in circuitry, a positive feedback or regenerative circuit
BORROW
a negative form of carry; see Carry; normally arising in direct subtraction by raising a lower order (less significant digit) and compensating by lowering a higher order digit e.g. when subtracting 67 from 92, a tens digit is "borrowed" from the 9, thus the 7 of 67 is subtracted from 12, yielding 5 as the units digit of the difference and then 6 is subtracted from 8 (or 9-1) yielding 2 as the tens digit. Thus, 25 is the difference.
BRANCH
a conditional jump; a point of decision in a program where a new routine or sub-routine is entered upon.
BREAKPOINT
a point in a routine at which the computer may, under the control of a manually-set switch, be stopped for a visual check of progress.
BUFFER
an isolating circuit used to avoid any reaction of a driven circuit upon the corresponding driving circuit, e.g. a circuit having an output and a multiplicity of inputs so designed that the output is energized whenever one or more inputs are energized. Thus, a buffer performs the circuit function or isolation which is equivalent to the logical "OR".
BUS
a path over which information is transferred; a trunk; an electrical conductor, channel or line; a heavy wire or heavy lead upon which many connections are made.
CABLE
an electrical conductor designed to provide common electric potential between two or more points.
CABLE, COAXIAL
a transmission line consisting of two conductors concentric with and insulated from each other.

BRL 1961, GLOSSARY, start page 1092

CALL-NUMBER
a set of characters identifying a subroutine and containing information concerning parameters to be inserted in the subroutine, information to be used in generating the subroutine, or information related to the operands; a call-word when exactly one word is filled.
CAPACITANCE
the property of two or more bodies which enables them to store electrical energy in an electrostatic field between the bodies; a measure of the ability to store electric charge.
CAPACITY
the upper and lower limits of the numbers which may be processed in a computer register, e.g., in the accumulator, e.g. the capacity of a computer may be ten decimal digits or the capacity of a computer may be +.00000 00001 to +.99999 99999. Quantities which exceed the capacity usually interrupt the operation of the computer in some fashion; the quantity of information which may be stored in a storage unit; see Capacity,Storage.
CAPACITY, STORAGE
maximum number of words or characters which a device is capable of storing; a measure of the ability of a device to store information for future reference.
CARD
heavy, stiff paper of uniform size and shape, adapted for being punched in an intelligible array of holes. The punched holes are sensed electrically by wire brushes, mechanically by metal feelers, or photoelectrically. One standard card, is 7 3/8 inches long by 3 and 1/1+ inches wide and contains 80 columns in each of which any one or more of 12 positions may be punched.
CARRIAGE, AUTOMATIC
a typewriting paper guiding or holding device which is automatically controlled by information and program so as to feed forms or continuous paper to a set of impression keys and to provide the necessary space, skip, eject, tabulate, or performing operations.
CARRIER WAVE
the basic frequency or pulse repetition rate of a signal, bearing no intrinsic intelligence until it is modulated by another signal which does bear intelligence. A carrier may be amplitude, phase, or frequency modulated. For example, in a typical mercury delay line memory of a digital computer, the 8 megacycle/second sound wave carrier is amplitude (pulse) modulated by a 1 megacycle/second pulse code signal, the presence or absence of a pulse determining whether or not a one or a zero is present in the binary number being represented.
CARRY
(1) A signal, or expression, produced as a result of an arithmetic operation on one digit place of two or more numbers expressed in Positional Notation and transferred to the next higher place for processing there; (2) Usually a signal or expression as defined in (1) above which arises in adding, when the sum of two digits in the same digit place equals or exceeds the Base of the number system in use. If a carry into a digit place will result in a carry out of of the same digit place, and if the normal adding circuit is bypassed when generating this new carry, it is called a High-Speed Carry, or Standing-on-Nines Carry. If the normal adding circuit is used in such a case, the carry is called a Cascaded Carry. If a carry resulting from the addition of carries is not allowed to propagate (e.g., when forming the partial product in one step of a multiplication process), the process is called a Partial Carry. If it is allowed to propagate, the process is called a Complete Carry. If a carry generated in the most significant digit place is sent directly to the least significant place (e.g., when adding two negative numbers using nine complements) that carry is called an End-Around Carry. (3) In direct subtraction, a signal or expression as defined in (1) above which arises when the difference between the digits is less than zero. Such a carry is frequently called a Borrow. (4) The action of forwarding a carry. (5) The command directing a carry to be forwarded.
CARRY, COMPLETE
see Carry
CARRY, CASCADED
see Carry
CARRY, HIGH-SPEED
see Carry
CARRY, PARTIAL
see Carry
CARRY, STANDING-ON-NINES
see Carry
CATHODE-FOLLOWER
a vacuum-tube circuit in which the input signal is applied to the control grid and the output is taken from the cathode, possessing high input impedance and low output impedance characteristics.
CELL
storage for one unit of information, usually one character or one word; a location specified by whole or part of the address and possessed of the faculty of store; specific terms such as column, field, location and block, are preferable when appropriate.
CELL, BINARY
an element that can have one or the other of two stable states or conditions and thus can store a single bit of information.

BRL 1961, GLOSSARY, start page 1093

CHANNEL
a path along which information, particularly a series of digits or characters, may flow. In storage which is serial by character and parallel by bit (e.g., a magnetic tape or drum in some codeddecimal computers), a channel comprises several parallel tracks. In a circulating storage a channel is one recirculating path containing a fixed number of words stored serially by word.
CHARACTER
one of a set of elementary symbols such as those corresponding to the keys on a typewriter. The symbols usually includes the decimal digits 0 through 9, the letters A through Z, punctuation marks, operation symbols, and any other single symbols which a computer may read, store, or write; a pulse code representation of such a symbol.
CHECK
a means of verification of information or operation during or after an operation.
CHECK, BUILT-IN AUTOMATIC
any provision constructed in "hardware" for verifying the accuracy of information transmitted, manipulated, or stored by any unit or device in a computer. Extent of automatic checking is the relative proportion of machine "hardware" devoted to checking.
CHECK, CODE
to check a particular coded problem for errors; to de-bug a code.
CHECK-DUPLICATION
a check which requires that the results of two independent performances (either concurrently on duplicate equipment or at a later time on the same equipment) of the same operation be identical.
CHECK-FORBIDDEN-COMBINATION
a Check (usually an Automatic Check) which tests for the occurrence of a nonpermissible code expression. A self-checking code (or error-detecting code) uses code expressions such that one (or more) error(s) in a code expression produces a forbidden combination. A parity check makes use of a selfchecking code employing binary digits in which the total number of l's (or O's) in each permissible code expression is always even or always odd. A check may be made for either even parity or odd parity. A redundancy check employs a self-checking code which makes use of redundant digits called check digits. Some of the various names that have been applied to this type of check are forbidden pulse combination, unused order (instruction) unallowable digits, improper operation code, improper command, false code, forbidden digit, non-existent code, and unused code.
CHECK, MATHEMATICAL or ARITHMETICAL
a check making use of mathematical identities or other properties, frequently with some degree of discrepancy being acceptable; e.g., checking multiplication by verifying that A,B = B.A, checking a tabulated function by differencing, etc.
CHECK, MODULO N
a form of check digits, such that the number of ones in each number A operated upon is compared with a check number B, carried along with A and equal to the remainder of A when divided by N, e.g., in a "modulo 4 check", the check number will be 0, 1, 2, or 3 and the remainder of A when divided by 4 must equal the reported check number B, or else an error or malfunction has occurred; a method of verification by congruences, e.g. casting out nines.
CHECK, ODD-EVEN
a check system in which a one or zero is carried along in a word depending on whether the total number of ones (or zeros) in a word is odd or even.
CHECK, PARITY
a summation check in which the binary digits, in a character or word, are added (modulo 2) and the sum checked against a single, previously computed parity digit; i.e., a check which tests whether the number of ones is odd or even.
CHECK, PROGRAMMED
a system of determining the correct program and machine functioning either by running a sample problem with similar programming and known answer, including mathematical or logical checks such as comparing A times B with B times A and usually where reliance is placed on a high probability of correctness rather than built-in error-detection circuits; a check system built into the actual program being run and utilized for checking during the actual running of the problem.
CHECK, REDUNDANT
a check which uses extra digits, short of complete duplication, to help detect malfunctions and mistakes.
CHECK, SUMMATION
a check in which groups of digits are summed, usually without regard for overflow, and that sum checked against a previously computed sum to verify accuracy.
CHECK, TRANSFER
verification of transmitted information by temporary storing, re- transmitting and comparing.
CHECK, TWIN
a continuous duplication check achieved by duplication of hardware and automatic comparison
CHECKING, MARGINAL
a system or method of determining computer circuit weaknesses and incipient malfunctions by varying the power applied to various circuits, usually by a lowering of the D.C. supply or filament voltages.

BRL 1961, GLOSSARY, start page 1094

CLAMING-CIRCUIT
a circuit which maintains either amplitude extreme of a waveform at a given voltage level, or potential.
CLEAR
to replace all information in a storage device by ones or zeros as expressed in the number system employed.
CLOCK, MASTER
the source of standard signals required for sequencing computer operation, usually consisting of a timing pulse generator, a cycling unit and sets of special pulses that occur at given intervals of time. Usually in synchronous machines the basic frequency utilized is the clocking pulse.
CLOSED-SHOP
this is intended to mean that mode of computing machine support wherein the applied programs and utility routines are written by members of a specific specialized group whose primary professional concern is the use of computers.
CODE
a system of symbols or their use in representing rules for handling the flow or processing of information; to actually prepare problems for solution on a specific computer.
CODE, COMPUTER
the code representing the operations built into the hardware of the computer; reperatoire of instructions.
CODE, EXCESS-THREE
a coded decimal notation for decimal digits which represents each decimal digit as the corresponding binary number plus three, e.g. the decimal digits 0, 1, 7, 9 are represented as 0011, 0100, 1010, 1100, respectively. In this notation, the nines complement of the decimal digit is equal to the ones complement of the corresponding four binary digits.
CODE, INSTRUCTION
an artificial language for describing or expressing the instructions which can be carried out by a digital computer. In automatically sequenced computers, the instruction code is used when describing or expressing sequences of instructions, and each instruction word usually contains a part specifying the operation to be performed and one or more addresses which identify a particular location in storage. Sometimes an address part of an instruction is not intended to specify a location in storage but is used for some other purpose. If more than one address is used, the code is called a multiple-address code.
CODE, INTERPRETER
a code which is acceptable to an interpretive routine.
CODE, MULTIPLE-ADDRESS
an instruction or code in which more than one address or storage location is utilized. In a typical instruction of a Four-Address Code the addresses specify the location of two operands, the destination of the result, and the location of the next instruction in the sequence. In a typical Three- Address Code, the fourth address specifying the location of the next instruction is dispensed with, the instructions are taken from storage in a preassigned order. In a typical Two-Address Code, the addresses may specify the locations of the operands. The results may be placed at one of the addresses or the destination of the results may be specified by another instruction.
CODE, OPERATIONAL
that part of an instruction which designates the operation to be performed.
CODING
the list, in computer code or in pseudo-code, of the successive computer operations required to solve a given problem; repertoire of instructions.
CODING, ABSOLUTE, RELATIVE or SYMBOLIC
coding in which one uses absolute, relative, or symbolic addresses, respectively, i.e., coding in which all addresses refer to an arbitrarily selected position, or in which all addresses are represented symbolically.
CODING, ALPHABETIC
a system of abbreviation used in preparing information for input into a computer such that information is reported in the form of letters, e.g., New York as NY, carriage return as CN, etc.
CODING, AUTOMATIC
any technique in which a computer is used to help bridge the gap between some "easiest" form, intellectually and manually, of describing the steps to be followed in solving a given problem and some "most efficient" final coding of the same problem for a given computer; two basic forms are Routine, Compilation and Routine, Interpretation.
CODING, NUMERIC
a system of abbreviation used in the preparation of information for machine acceptance by reducing all information to numerical quantities; in contrast to alphabetic coding.
COLLATE
to combine two or more similarly ordered sets of items to produce another ordered set composed of information from the original sets. Both the number of items and the size of the individual items in the resulting set may differ from those of either of the original sets and of their sums, sequence 23, 24, 48 may be collated into 12, 23, 24, 29, 42, 48; to combine two or more sequences of items according to a prescribed rule such that all items appear in the final sequence.

BRL 1961, GLOSSARY, start page 1095

COLLATOR
a machine which has two card feeds, four card pockets and three stations at which a card may be compared or sequenced with regard to other cards so as to select a pocket in which it is to be placed, e.g., the machine is suitable for matching detail cards with master cards, merging cards in proper sequence, etc.
COLUMN
one of the character or digit positions in a positional notation representation of a unit of information, columns are usually numbered from right to left column, zero being the right-most column if there is no point, or the column immediately to the left of the point if there is one; a position or place in a number in which the position designates the power of the base and the digit is the coefficient, e.g.., in 3876, the 8 is the coefficient of 10 , the position of the 8 designating the 2.
COMMAND
a pulse, signal, or set of signals initiating one step in the performance of a computer operation; that portion of the instruction word which specifies the operation to be performed; See instruction and order.
COMPARATOR
a device for comparing two different transcriptions of the same information to verify the accuracy of transcription, storage, arithmetic operation or other process, in which a signal is given dependent upon the relative state of two items, i.e. larger, smaller, equal, difference, etc.
COMPARE
to examine the representation of a quantity for the purpose of discovering its relationship to zero, or of two quantities usually for the purpose of discovering identity or relative magnitude.
COMPARISON
determining the identity, relative magnitude and relative sign of two quantities usually in order to initiate an action.
COMPARISON, LOGICAL
the operation concerned with the determination of similarity or dissimilarity of two items, e.g. if A and B are alike, the result shall be"1" or.yes, if A and B are not alike or equal, the result shall be "0" or no, signifying "not alike".
COMPILER
a program making routine, which produces a specific program for a particular problem by determining the intended meaning of an element of information expressed in pseudo-code, selecting or generating the required subroutine, transforming the subroutine into specific coding for the specific problem, assigning specific storage registers, etc. and entering it as an element of the problem program, maintaining a record of the subroutines used and their position in the problem program and continuing to the next element of information in pseudo-code.
COMPLEMENT
a quantity which is derived from a given quantity, expressed to the base n, by one of the following rules and which is frequently used to represent the negative of the given quantity. (a.) Complement on n; subtract each digit of the given quantity from n-1, add unity to the least significant digit, and perform all resultant carrys. For example, the twos complement of binary 11010 is 00110; the tens complement of decimal 456 is 544. (b) Complement' on n-1: subtract each digit of the given quantity from n-1. For example, the ones complement of binary 11010 is 00101; the nines complement of decimal 456 is 543.
COMPUTER
any device capable of accepting information, applying prescribed processes to the information, and supplying the results of these processes; sometimes, more specifically, a device for performing sequences of arithmetic and logical operations; sometimes, still more specifically, a stored-program digital computer capable of performing sequences of internally-stored instructions, as opposed to calculators on which the sequence is impressed manually desk calculator) or from tape or cards (card programmed calculator).
COMPUTER, ANALOG
a calculating machine which solves problems by translating physical conditions like flow, temperature or pressure into electrical quantities and using electrical equivalent circuits for the physical phenomenon.
COMPUTER, ASYNCHRONOUS
a calculating device in which an operation is initiated by a signal generated upon completion of a previous operation; contrasted with Synchronous Computer.
COMPUTER, AUTOMATIC
a calculating device which handles long sequences of operations without human intervention.
COMPUTER, DIGITAL
a calculating device utilizing numbers to express all the variables and quantities of a problem. The numbers are usually expressed as a space-time distribution of punched holes, electrical pulses, sonic pulses, etc.
COMPUTER, SYNCHRONOUS
a calculating device in which the performance of all operations is controlled with periodic signals from a master clock.
CONJUNCTION
in logical design, normally an "And" function; see And-Operator.
CONTENTS
the information stored in any storage medium. Quite prevalently, the symbol ) is used to indicate "the contents of"; e,g., (m) indicates the contents of the storage location whose address is m; (A) indicates the contents of register A; (T2) may indicate the contents of the tape on inputoutput unit two.

BRL 1961, GLOSSARY, start page 1096

CONTROL
(1) Usually, those parts of a digital computer which effect the carrying out of instructions in proper sequence, the interpretation of each instruction, and the application of the proper signals to the arithmetic unit and other parts in accordance with this interpretation. (2) Frequently, one or more of the components in any mechanism responsible for interpreting and carrying out manually-initiated directions. Sometimes called manual control. (3) In some applications of mathematics, a mathematical check.
CONTROL, CASCADE
an automatic control system in which various control units are linked in sequence, each control unit regulating the operation of the next control unit in line.
CONTROL-SEQUENCE
the normal order of selection of instructions for execution. In some computers, one of the addresses in each instruction specifies the control sequence. In most other computers the sequence is consecutive except where a Jump occurs.
CONTROL, SEQUENTIAL
a manner of operation of a computer such that instructions are fed to or stored in the computer in a given order during the solution of a problem and the computer executes these instructions in a given order.
CONTROL-UNIT
that portion of the hardware of an automatic digital computer which directs the sequence of operations, interprets the coded instructions, and initiates the proper commands to the computer circuits to execute the instructions.
CONVERT
to change numerical information from one number base to another (e.g., decimal to binary) and/or from some form of fixed point to some form of floating-point representation, or vice versa; occasionally to transfer information from one recorded medium to another.
CONVERTER
a unit which changes the language of information from one form to another so as to make it available or acceptable to another machine, e.g., a unit which takes information punched on cards to information recorded on magnetic tape, possibly including editing facilities.
COPY
to reproduce information in a new location, replacing whatever was previously stored there, and usually leaving the information unchanged at the original location.
CORE, MAGNETIC
a magnetic material capable of assuming and remaining at one of two or more conditions of magnetization, thus capable of providing storage, gating or switching functions, usually of toroidal shape and pulsed or polarized by electric currents carried on wire adjacent the material.
COUNTER
a device, register, or storage location for storing numbers or integers, permitting these integers to be increased or decreased by unity or by an arbitrary number or integer, and capable of being reset to zero or to an arbitrary number.
COUNTER, CONTROL
a device which records the storage location of the instruction word, which is to be operated upon following the instruction word in current use. The control counter may select storage locations in sequence, thus obtaining the next instruction word from the subsequent storage location, unless a transfer or special instruction is encountered.
COUNTER, RING
a loop of interconnected bistable elements such that one and only one is in a specified state at arty given time and such that, as input signals are counted, the position of the element in the specified state "moves" in an ordered sequence around the loop.
COUPLING
the means by which energy is transferred from one circuit to another; the common impedance necessary for coupling.
COUPLING, CAPACITIVE
a method of transferring energy from one circuit to another by means of a capacitor that is common to both circuits.
COUPLING, DIRECT
a method of transferring energy from one circuit to another by means of resistors common to both circuits.
CRT
cathode-ray tube; a device yielding a visual plot of the variation of several parameters by means of a proportionally deflected beam of electrons.
CYBERNETICS
the comparative study of the control and intracommunication of information handling machines and nervous systems of animals and man in order to understand and improve communication.
CYCLE
a set of operations repeated as a unit; a nonarithmetic shift in which the digits dropped off at one end of a word are returned at the other end in circular fashion; cycle right and cycle left. To repeat a set of operations a prescribed number of times including, when required, supplying necessary address changes by arithmetic processes or by means of a hardware device such as a B-box or cycle-counter.
CYCLE COUNT
to increase or decrease the cycle index by unity or by an arbitrary integer or number.

BRL 1961, GLOSSARY, start page 1097

CYCLE-CRITERION
the total number of times the cycle is to be repeated; the register which stores that number.
CYCLE-INDEX
the number of times a cycle has been executed; or the difference, or the negative of the difference, between that number and the number of repetitions desired.
CYCLE, MAJOR
the maximum access time of a recirculating serial storage element; the time for one rotation, e.g., of a magnetic drum or of pulses in an acoustic delay line; a whole number of minor cycles.
CYCLE, MEMORY
a repeated, periodic sequence of events occurring when information is transferred to or from the storag device of a computer. Storing, sensing, and regeneration form parts of the storage sequence. Usually a"timing chart,' shoving pulse times on all leads to a storage cell describe such a cycle.
CYCLE, MINOR
the word time of a serial computer, including the spacing between words.
CYCLE, RESET
to return a cycle index to its initial value.
DAMPING
a characteristic built into electrical circuits and mechanical systems to prevent rapid or excessive corrections which may lead to instability or oscillatory conditions, e.g., connecting a resistor on the terminals of a pulse transformer to remove, natural oscillations; placing a moving element in oil or sluggish grease to prevent overshoot.
DATA-REDUCTION
the art or process of transforming masses of raw test or experimentally obtained data, usually gathered by instrumentation, into useful, ordered, or simplified intelligence.
DATA-REDUCTION, ON-LINE
the processing of information as rapidly as the information is received by the computing system or as rapidly as it is generated by the source.
DEBUG
to isolate and remove all malfunctions from a computer or all mistakes from a routine.
DECADE
a group or assembly of ten units, e.g., a decade counter counts to ten in one column; a decade resistor box inserts resistance quantities in multiples of powers of 10; ten years.
DECIMAL, CODED, BINARY
decimal notation in which the individual decimal digits are represented by some binary code, e.g., in the 8-4-2-1 coded decimal notation, the number twelve is represented as 0001 0010 for 1 and 2, respectively, whereas in pure binary notation, it is represented as 1100. Other coded decimal notations are used, e.g., 5-4-2-1, excess three, 2-4-2-1, etc.
DECODE
to ascertain the intended meaning of the individual characters or groups of characters in the pseudo-coded program.
DECODER
a device capable of ascertaining the significance or meaning of a group of signals and initiating a computer event based thereon; matrix.
DECREMENT-FIELD
a portion of an instruction word set aside specifically for modifying the contents of a register or memory location specified by the tag digits of the same instruction word.
DEFLECTION-SENSITIVITY
in connection with Cathode Ray Tubes, it is the quotient of the displacement of the electron beam at the place of impact by the change in deflecting as was. It is usually expressed in millimeters per volt applied between the deflection electrodes, or in millimeters per gauss of the deflecting magnetic field.
DELAY-LINE, ELECTRIC
a transmission line of lumped or distributed capacitive and inductive elements in which the velocity of propagation of electromagnetic energy is small compared with the velocity of light. Storage may be accomplished by re-circulation of wave patterns containing information, usually in binary form.
DELAY-LINE, MAGNETIC
a magnetic medium along which the velocity of propagation of magnetic energy is small relative to the speed of light. Storage is accomplished by recirculation of wave patterns containing information, usually in binary form.
DELAY-LINE, MERCURY or QUARTZ
a sonic or acoustic delay-line in which mercury or quartz is used as the medium of sound transmission, with transducers on each end to permit conversion to and from electrical energy; See Delay-line, Sonic or Acoustic.
DELAY-LINE, SONIC or ACOUSTIC
a device capable of transmitting retarded sound pulses, transmission being accomplished by wave patterns of elastic deformation. Storage is accomplished by re-circulation of wave pattern containing information, usually in binary form.
DENSITY, PACKING
the number of units of useful information contained within a given linear dimension, usually expressed in units per inch, e.g., the number of binary digit magnetic pulses stored on tape or drum per linear inch on a single track by a single head.

BRL 1961, GLOSSARY, start page 1098

DESIGN, LOGICAL
(1) The planning of a computer or data-processing system prior to its detailed engineering design.(2) The synthesizing of a network of logical elements to perform a specified function. (3) The result of (1) and (2) above, frequently called the logic of the system, machine, or network.
DIAGRAM, BLOCK
a schematic representation of a sequence of subroutines designed to solve a problem; a coarser and less symbolic representation than a flow chart, frequently including descriptions in English words; a schematic or logical drawing showing the electrical circuit or logical arrangements within a component.
DIAGRAM, LOGICAL
in logical design a diagram representing the logical elements and their interconnections without necessarily expressing construction or engineering details.
DIFFERENTIATOR
a device whose output function is proportional to a derivative of its input function with respect to one or more variables.
DIGIT
one of the n symbols of integral value ranging from 0 to n-1 inclusive in a scale of numbering of base n, e.g., one of the ten decimal digits, 0, 1, 2. 3, 4, 5. 6, 7, 8,, 9.
DIGIT, BINARY
a whole number in the binary scale of notation; this digit may be only 0 (zero) or 1 (one). It may be equivalent to an "on" or "off" condition, a "yes" or a "no", etc.
DIGIT, DECIMAL, CODED
one of ten arbitrarily-selected patterns of ones and zeros used to represent the decimal digits.
DIGITAL
the quality of utilizing numbers in a given scale of notation to represent all the quantities that occur in a problem or a calculation.
DIGITIZE
to render an analog measurement of a physical variable into a numerical value, expressing the quantity in digital form.
DIGITS, EQUIVALENT BINARY
the number of binary digits required to express a number in another base with the same precision, e.g., approximately 3 1/3 times the number of decimal digits is required to express a decimal number in binary form. For the case of coded decimal notation, the number of binary digits required is 4 times the number of decimal digits.
DISJUNCTION
in logical design, normally an "OR" function; see OR-Operator
DOWN-TIME
the period during which a computer is malfunctioning or not operating correctly due to machine failures; contrasted with available time, idle time or standby time. Scheduled maintenance time is also considered down-time, in as much as the computer is unable to operate during this period.
DRUM, MAGNETIC
a rotating cylinder on whose magnetic-material coating information is stored in the form of magnetized dipoles, the orientation or polarity of which is used to store binary information.
DUMMY
an artificial address, instruction, or other unit of information inserted solely to fulfill prescribed conditions (such as word-length or block-length) without affecting operations..
DUMP, A. C. the removal of all A. C. power, intentionally, accidentally or conditionally from a system or component. An A. C. dump usually results in the removal of all power. DUMP, D. C. the removal of all D.C. power, intentionally, accidentally, or conditionally, from a system. or component.
DUMP, POWER
the removal of all power accidentally or intentionally.
ECCLES-JORDAN (TRIGGER)
a direct coupled multivibrator circuit possessing two conditions of stable equilibrium. Also known as a flip-flop circuit or "toggle".
ECHO CHECKING
a system of assuring accuracy by reflecting the transmitted information back to the transmitter and comparing the reflected information with that which was transmitted.
EDIT
to rearrange information. Editing may involve the deletion of unwanted data, the selection of pertinent data, the insertion of invariant symbols such as page numbers and typewriter characters, and the application of standard processes such as zerosuppression.
ELECTRONIC
pertaining to the application of that branch of science which deals with the motion, emission and behavior of currents of free electrons, especially in vacuum, gas or phototubes and special conductors or semi-conductors. Contrasted with electric which pertains to the flow of large currents in wires or conventional conductors.

BRL 1961, GLOSSARY, start page 1099

ELEMENT, LOGICAL
in a computer or data-processing system, the smallest building blocks which can be represented by operators in an appropriate system of symbolic logic. Typical logical elements are the and-gate and the flip- flop, which.can be represented as operqtors in a suitable symbolic logic.
ELEVATION
the angular measurement in a vertical plane from a specific reference, usually the horizontal plane.
ENCODER
a network or system in which usually one input is excited at a time and each input produces a combination of outputs. Sometimes called matrix.
ERASE
to replace all the binary digits in a storage device by binary zeros. In a binary computer, erasing is equivalent to clearing, while in a coded decimal computer where the pulse code for decimal zero may contain binary ones, clearing leaves decimal zero while erasing leaves all-zero pulse codes.
ERROR
the amount of loss of precision in a quantity; the difference between an accurate quantity and its calculated approximation; errors occur in numerical methods, e.g. an error introduced by the truncation of a power series defining a tranacen dental function. This may be classified as an error introduced by the numerical method, there is no mistake involved and the computer is operating properly; mistakes occur in programming. coding data transcritpion. and operating; thus, usually .humans make mistakes, e.9ù, assigning a wrong address -vnen cooing a problem; malfunctions occur in computers and are due to physical limitations on the properties of materials. An error is sometimes considered to be the differential margin by which a controlled unit deviates from its target value.
ERROR, INHERITED
the error in the initial values; especially the error inherited from the previous steps in the step-by-step integration. This error could also be the error introduced by the inability to make exact measurements of physical quantities.
ERROR, ROUNDING
the error resulting from deleting the less significant digits of a quantity and applying some rule of correction to the part retained. A common round- off rule is to take the quantity to the nearest digit. Thus, pi, 3.14159265..., rounded to four decimals is 3.1416. Note; Alston S. Householder suggests the following terms: "initial errors","generated errors", propagated errors" and "residual errors". If x is the true value of the argument, and x^* the quantity used in computation, then assuming one wishes f(x), x-x* is the initial error; f(x) - f(x^*) is the propagated error. If f_a is the Taylor, or other, approximation utilized, then f(x^* - f_a(x^*) is the residual error. If f^* is the actual result then f_a - f^* is the generated error, and this is what builds up as a result of rounding.
ERROR, TRUNCATION
the error resulting from the use of only a finite number of terms of an infinite series, or from the approximation of operations in the infinitesimal calculus by operations in the calculus of finite differences.
EXCHANGE to interchange the contents of two storage devices or locations.
EXCLUSIVE-OR-OPERATOR
a logical operator which has the property that if P and Q are two statements, then the statement P # Q (i.e. ~ is Exclusive-Or Operator) is true or false depending whether the variables are odd or even, e. g.
```
              P     Q     P # Q
              0     1       1    (odd)
              1     0       1    (odd)
              1     0       1    (even)
              0     0       0    (even)
   
```
Note that the Exclusive-OR is the same as the Inclusive-Or, except that the case for both inputs present yields no output. See Inclusive-OR; P # Q is True if P or Q are true, but not both. Primarily used in comparator circuits.
EXTRACT
to remove from a set of items of informatinn all those items that meet some arbitrary criterion; to replace the contents of specific parts of a quantity (as indicated by some other quantity called an extractor) by the contents of specific parts of a third quantity, e.g., if the number 01101 is stored, the machine can remove and act upon or according to the third digit,. in this case a 1.
FACTOR, SCALE
one or more coefficients used to multiply or divide quantities in a problem in order to oonvert them so as to have them lie in a given range of magnitude, e.g., plus one to minus one.
FEED, CARD
a mechanism which moves cards serially into a machine.
FERROELECTRIC
a phenomenon exhibited by materials within which permanent electric dipoles exist and a residual displacement in the D-E plane occurs, where D = E + 4(pi)P (vectorial), in which D is the electric displacement vector, E is the applied electric field strength and P is a measure of the degree of polarization. Thus, E is measurable, e.g., as potential difference per unit length force per unit charge, or lines of force per unit area. The polarization P, is measured in dipoles per unit volume or charge moved across a unit area upon application of an electric field. In ferroelectric materials there is a residual polarization, Pr . Note the similarity for ferromagnetics: B = H + 4(pi)M where B is the magnetic induction, i.e. total lines of force per unit area, H is the magnetic field intensity usually produced by a distribution of electric currents and M is the magnetic polarization. It is because of the similarity of behavior, described by these two equations, that the phenomenon of ferroelectricity is described using the prefix "ferro", i.e. "pertaining to or like unto iron".

BRL 1961, GLOSSARY, start page 1100

FERROMAGNETICS
in computer technology, the science that deals with the storage of information and the logical control of pulse sequences through the utilization of the magnetic polarization properties of materials to store binary information. FIELD a set of one or more characters (not necessarily all lying on the same word) which is treated as a whole; a set of one or more columns on a punched card consistently used to record similar information.
FIELD, CARD
a set of card columns fixed as to number and position into which the same type of information is regularly entered.
FIELD, DECREMENT
a portion of an instructor word set aside specifically for modifying the contents of a register or memory location specified by the tag digits of the same instructor word.
FILE
a sequential or organized set of items.
FIXED-POINT
a notation or system of arithmetic in which all numerical quantities are expressed by a predetermined number of digits with the arithmetic point implicitly located at some pre- determined position; contrasted with floating-point.
FLIP-FLOP
a bi-stable device; a device capable of assuming two stable states; a bi-stable device which may assume a given stable state depending upon the pulse history of one or more input points and having one or more output points. The device is capable of storing a bit of information; a control device for opening or closing gates; a toggle. See Eccles-Jordan.
FLOATING-POINT
a notation in which a number x is represented by a pair of numbers y and z (and two integers n and m which are understood parameters, m being the number base to which y is expressed and n the base of the exponent z, in any given representation) with y and z chosen so that x = y.n^z where z is an integer and where m and n are usually 2 or 10. The quantity y is called the fractional or mantissa; the integer z is called the exponent or characteristic, e.g. a decimal number 241,000,000 might be shown as 2.41, 8, since it is equal to 2.41 x 108. Here the 2.41 is assumed to be the base 10.
FLOW-CHART
a graphical representation of a sequence of operations, using symbols to represent the operations such as compute, substitute, compare, jump, copy, read, write, etc., A flow chart is a more detailed representation than a diagram.
FORCE
to intervene manually in a routine and cause the computer to execute a jump instruction.
FOUR-ADDRESS
see Code, Multiple-address.
FUNCTION-TABLE
two or more sets of information so arranged that an entry in one set selects one or more entries in the remaining sets; a diectionary; a device constructed of hardware, or a subroutine, which can either (a) decode multiple inputs into a single output or `b) encode a single input into multiple outputs; a tabulation of the values of a function for a set of values of the variable.
FUNCTOR
a logical element which performs a specific function or provides a linkage between variables. Usage not recommended.
GATE
a circuit which has the ability to produce an output which is dependent upon a specified type of or the co-incidence nature of the input, e.g. an "and" gate has an output pulse when there is time coincidence at all inputs; and "or" gate has an output when any one or any combination of input pulses occur in time coincidence; any gate may contain a number of "inhibits", in which there is no output under any condition of input if there is time coincidence of an inhibit or "except" signal.
GENERATOR
a program for a computer which generates the coding of a problem; a mechanical device which produces an electrical output.
GRID, CONTROL
the electrode of a vacuum tube other than a diode upon which a signal voltage is impressed in order to control the plate current; usually electrode number 1.
HALF-ADDER
a circuit having two output points, S and C, and two input points, A and B, such that the output is related to the input according to the following table:
```
        INPUT       OUTPUT
       A    B       S    C
       0    0       0    0
       0    1       1    0
       1    0       1    0
       1    1       0    1
    
```
If A and B are arbitrary input pulses, and S and C are "sum without carry" and carry, respectively, it may be seen that two half-adders, properly connected may be used for performing binary addition.

BRL 1961, GLOSSARY, start page 1101

HARDWARE
the mechanical, magnetic, electronic and electrical devices from which a computer is fabricated; the assembly of material forming a computer or component thereof. HEAD a device which reads, records or erases information in a storage medium, usually a small electromagnet used to read, write or erase information on a magnetic drum or tape or the set of perforating or reading fingers and block assembly for punching or reading holes in paper tape or cards.
HOLD
the function of retaining information in one storage device after transferring it to another device; in contrast to clear.
HUNTING
a continuous attempt on the part of an automatically controlled system to seek a desired equilibrium condition. The system usually contains a standard, a method of determining deviation from this standard and a method of influencing the system such that the difference between the standard and the state of the system is brought to zero. See Servomechanism.
IGNORE
an instruction requiring non-performance of what normally might be executed; not to be executed; a typewriter character indicating that no action whatsoever be taken. (In Teletype or Flexowriter code, all holes punched is an ignore).
IMPEDANCE, CHARACTERISTIC
the ratio of voltage to current at every point along a transmission line on which there are no standing waves; the square root of the product of the open and short circuit impedance of the line. When a transmission line is terminated in its characteristic impedance, energy is not reflected, but is fully absorbed in the terminating impedance.
INCLUSIVE-OR-OPERATOR
see OR-OPERATOR. P or Q is True if P or Q or both is True; when the term OR is used alone, as in OR-gate, the Inclusive-OR is usually implied; buffer. INFORMATION an aggregation of data.
INPUT
the information which is transferred from external storage into the internal storage; a modifier designating the device performing this function.
INSTRUCTION
a set of characters which defines an operation together with one or more addresses (or no address) and which, as a unit, causes the computer to operate accordingly on the indicated quantities. The term "instruction" is preferable to the terms "command" and "order"; command is reserved for electronic signals; order is reserved for "the order of the characters" (implying sequence) or "the order of the interpolation", or "the order of the differential equation".
INSTRUCTION, BREAKPOINT
an instruction which, if some specified switch is set, will cause the computer to stop.
INSTRUCTION, BREAKPOINT, CONDITIONAL
a conditional jump instruction which, if some specified switch is set or situation exists, will cause the computer to stop, after which either the routine may be continued as coded or a jump may be forced.
INSTRUCTION, MULTIPLE-ADDRESS
see code, Multiple-address.
INSTRUCTION, ONE-ADDRESS
an instruction consisting of an operation and exactly one address. The instruction code of a single-address computer may include both zeroand multi-address instructions as special cases.
INSTRUCTION, ONE-PLUS-ONE or THREE-PLUS-ONE ADDRESS
a two- or four-address instruction, respectively, in which one of the addresses always specifies the location of the next instruction to be performed.
INSTRUCTION, TRANSFER
a computer operational step in which a signal or set of signals specifies the location of the next operation to be performed and directs the computer to that operation (or instruction).
INSTRUCTION, TWO, THREE or FOUR ADDRESS
an instruction consisting of an operation and 2, 3, or 4 addresses, respectively. The addresses may specify the location of operands, destination of results, or location of other or next instruction.
INSTRUCTION, ZERO-ADDRESS
an instruction specifying an operation in which the location of the operands are defined by the computer code, so that no address need be given explicitly.
INTEGRATOR
a device whose output is proportional to the integral with respect to the input variable.
INTERLACE
to assign successive storage locations to physically separated storage positions, e.g. on a magnetic drum or tape, usually for the express purpose of reducing access time.

BRL 1961, GLOSSARY, start page 1102

ITEM
a set of one or more fields containing related information; a unit of correlated information relating to a single person or object; the contents of a single message.
INTERPRETER
an interpretive routine.
JUMP
an instruction or signal which, conditionally or unconditionally, specifies the location of the next instruction and directs the computer to that instruction. A jump is used to alter the normal sequence control of the computer. Under certain special conditions, a ,jump may be forced by manual intervention. In other words a transfer of control is made to a specified instruction.
JUMP, CONDITIONAL
an instruction which will cause the proper one of two (or more) addresses to be used in obtaining the next instruction, depending upon some property of one or more numerical expressions or other conditions.
KEY
a group of characters usually forming a field, utilized in the identification or location of an item; a marked lever manually operated for copying a character, e.g. typewriter, paper tape perforator, card punch manual keyboard, digitizer or manual word generator.
LAG
a relative measure of the time delay between two events, states, or mechanisms.
LANGUAGE, MACHINE
expressions which define the operations of a computer, usually intelligible to the computer by means of its circuitry. It may be information recorded in a form which many be made available to a computer; coded information which can be sensed by a machine.
LATENCY
in a serial storage system, the access time less the word time, e.g. the time spent waiting for the desired word or unit of information to appear under the drum heads or at the end of an acoustic tank.
LIBRARY, ROUTINE
an ordered set or collection of standard and proven routines and subroutines by which problems and parts of problems may be solved, usually stored in relative or symbolic coding. (A library may be subdivided into various volumes, such as floating decimal, double-precision, or complex, according to the type of arithmetic employed by the subroutines.)
LINE, DELAY
a device capable of causing an energy impulse to be retarded in time from point to point, thus providing a means of storage by circulating intelligence bearing- pulse configurations and patterns. Examples of delay lines are material media such as mercury, in which sonic patterns may be propagated in time; lumped constant electrical lines; co-axial cables, transmission lines and recirculating magnetic drum loops.
LINE-PRINTING
printing an entire line of characters across a page as the paper feeds in one direction past a type bar or cylinder bearing all characters on a single element.
LINE, TRANSMISSION
any conductor or systems of conductors used to carry electrical energy from its source to a load.
LOCATION
a unit storage position in the main internal storage, storing one computer word; a storage register.
LOCATION, STORAGE
a storage position holding one computer word, usually designated by a specific address or a specific register.
LOGGER
a device which automatically records physical processes and events, usually chronologically.
LOGIC
the science that deals with the canons and criteria of validity in thought and demonstration; the science of the formal principles of reasoning; the basic principles and applications of truth tables, gating, interconnection, etc. required for arithmetic computation in a computer.
LOGIC, SYMBOLIC
exact reasoning about relations using symbols that are efficient in calculation. A branch of this subject known as Boolean algebra has been of considerable assistance in the logical design of computing circuits.
LOGICAL
see Operation, Logical.
LOOP
the repetition of a group of instructions in a routine.
LOOP, CLOSED
repetition of a group of instructions which may be repeated indefinitely.

BRL 1961, GLOSSARY, start page 1103

MALFUNCTION
a failure in the operation of the hardware of a computer. See Error.
MATRIX
in mathematics, an array of quantities in a prescribed form, usually capable of being subject to a mathematical operation by means of an operator or another matrix according to orescribed rules; an array of circuit elements, e.g. diodes, wires, magnetic cores, relays, etc. which are capable of performing a specific function, e.g. conversion from one numerical system to another or selection of a channel based upon the input signal pattern.
MEMORY
the term "storage" is preferred.
MERGE
to produce a single sequence of items, ordered according to some rule (i.e., arranged in some orderly sequence), from two or more sequences previously ordered according to the same rule, without changing the items in size, structure, or total number. Merging is a special case of collation.
MESSAGE
a group of words, variable in length, transported as a unit; a transported item of information.
MICROSECOND
a millionth part of a second. Abbreviated usec.
MILLISECOND
a thousandth part of a second. Abbreviated msec.
MISTAKE
a human blunder which results in an incorrect instruction in a program or in coding, an incorrect element of information, or an incorrect manual operation. See Error.
MNEMONIC
assisting, or intended to assist, memory; of or pertaining to memory; mnemonics is the art of improving the efficiency of the memory (in computers, storage).
MODIFIER
a quantity used to alter the address of an operand, e.g. the cycle index.
MODIFY
in an instruction, to alter the address of the operand; to alter a subroutine according to a defined parameter.
MULTIVIBRATOR
a type of relaxation oscillator used for the generation of non-sinusoidal waves in which the output of each of its two tubes is coupled to the input of the other to sustain oscillations.
MULTIVIBRATOR, ASTABLE
a free running type of relaxation oscillator used for the generation of non-sinusoidal waves.
MULTIVIBRATOR, MONOSTABLE
a type of relaxation oscillator used to sustain a trigger pulse for a specified time. The device assumes another state for a specified length of time at the end of which it returns to its original state, after being pulsed or forced into another state.
NORMALIZE
to adjust the exponent and mantissa of a floating-point result so that the mantissa lies in the prescribed standard (normal) range; standardize.
NOTATION
see "NUMBER-SYSTEM".
NOTATION, BIQUINARY one of any number of mixed-base notations in which the term nⁱ in the definition of number system is replaced by the product ono mJ* In the biquinary system, m_j is two for j odd, five for j even; a scale of notation wherein the base is alternately 2 and 5, e.g. the decimal number 3671 is biquinary 03 11 12 01, the first of each pair of digits counting 0 or 1 units of five and the second counts 0, 1, 2, 3 or 4 units. For comparison, the same number in Roman numerals is MMMDCLXXI Biquinary notation expresses the representation of numbers by the abacus, and by the two hands and five fingers of man and is used in some computers.
NOTATION, CODED-DECIMAL
decimal notation in which the individual decimal digits are represented by some code.
NOTATION, MIXED-BASE
a number system in which the term nⁱ in the definition of number-system is replaced by the product ??? m_j, e.g. in the biquinary system m_j is two for j odd and five for j even.
NOTATION, POSITIONAL
in a number system, a notation in which the position of each digit determines the exponent to which the base is raised, the digit being the coefficient of the power of the base and the position of the digit indicating the power to which the base is raised, e.g. in decimal, positional notation, 264 is 2 x 10² + 6 x 10¹ + 4 x l0⁰.

BRL 1961, GLOSSARY, start page 1104

NUMBER, BINARY
a numerical value written in the base-two system of notation. Usually the characters 0 and 1 are used to express numbers, although any pair of arbitrary symbols could be used. NUMBER, OPERATION a number indicating the position of an operation or its equivalent subroutine in the sequence forming a problem routine. When a problem is stated in pseudo-code, each step is sometimes assigned an operation number.
NUMBER, RANDOM
a set of digits constructed of such a sequence that each successive digit is equally likely to be any of n digits to the base n of the number.
NUMBER-SYSTEM
numerical notation; positional notation; a systematic method for representing numerical quantities in which any quantity is represented approximately by the factors needed to equate it to a sum of multiples of powers of some chosen base n. That is, a number x = a_qn^q+a_q-1n^q-1 +...+a₁n+a_o+a_-1n^-1 1+...+a-pn p 1=q 1 _ Sumation sin , with n < a_i 0 for all i, is repre sented by aqaq- l...ala0a-l_a-p, with a point to the right of a 0 to identify it. For example, in decimal notation familiar to all, in which n equals ten, x = 371.426 represents 3-102 + 7ù101 + 1.100 + 4ù10 1 + 2.10 2 + 6ù10 3; in binary notation, in which n equals two, x = 1101.01 represents 1ù23 + 1-22 + 0.21 + 1-20 + 0.2 1 + 1.2 2, which = 13ù75 in decimal notation. In writing numbers, the base is sometimes indicated as a subscript (itself always in decimal notation) whenever there is any doubt about what base is being employed (e.g-, 1101.112 = 13.7510); Binary, Ternary, Quatenary, Quinar , Octal (Octonary), Decimal, Duodecimal, Sexadecimal Hexadecimal or Duotricenary Notation notation using the base 2, 3, 4, 5, 8, 10, 12, 16 or 32 respectively.
OCTAL
pertaining to the number base of eight, e.g. in octal notation, octal 214 is 2 times 64 plus 1 times 8 plus 4 times 1 equals decimal 140; octal 214 is binary-coded-octal 010, 001, 100; octal 214 is straight binary 10001100.
ONE-ADDRESS
single address; a system of machine instruction such that each complete instruction explicitly describes one operation and one storage location. See Instruction, One-Address.
ON-LINE OPERATION
a type of system application in which the input data to the system is fed directly from the measuring devices and the computer results obtained during the progress of the event, e.g. a computer receives data from wind tunnel measurements during a run, and the computations of dependent variables are performed during the run enabling a change in the conditions so as to produce particularly desirable results. OPERAND any one of the quantities entering or arising in an operation. An operand may be an argument, a result, a parameter, or an indication of the location of the next instruction; generally, the quantity being operated upon.
OPERATION
a defined action; the action specified by a single computer instruction or pseudo-instruction; an arithmetical, logical, or transferal unit of a problem, usually executed under the direction of a subroutine.
OPERATION, ARITHMETICAL
an operation in which numerical quantities form the elements of the calculation (e.g addition, subtraction, multiplication, division).
OPERATION, AVERAGE-CALCULATING
a common or typical calculating operation longer than an addition and shorter than a multiplication; often taken as the average of nine addition and one multiplication time.
OPERATION, COMPLETE
an operation which includes (a) obtaining the instruction, (b) obtaining all operands from storage, (c) performing the operation, and (d) returning results to storage.
OPERATION, COMPUTER
the electronic action resulting from an instruc- tion; in general, computer manipulation required to secure computed results.
OPERATION, FIXED-CYCLE
a type of computer performance whereby a fixed amount of time is allocated to an operation; synchronous or clock-type arrangement within a computer in which events occur as a function of measured time.
OPERATION, LOGICAL
an operation in which logical (yes-or-no) quantities form the elements being operated on (e.g., comparison, extraction). A usual requirement is that the value appearing in a given column of the result shall not depend on the values appearing in more than one given column of each of the arguments.

BRL 1961, GLOSSARY, start page 1105

OPERATION, REAL-TIME or ON-LINE
the processing of data in synchronism or in coincidence with a physical process in such a fashion that the results of the data-processing are useful to the physical operation.
OPERATION, RED-TAPE
an operation which does not directly contribute to the result; i.e., arithmetical, logical, and transfer operations used in modifying the address section of other instructions in counting cycles, in rearranging data, etc.
OPERATION, SERIAL
the flow of information through a computer in time sequence, using only one digit, word, line or channel at a time. Contrasted with parallel operation.
OPERATION, TRANSFER
an operation which moves information from one storage location or one storage medium to another (e.g., read, record, copy, transmit, exchange). Transfer is sometimes taken to refer specifically to movement between different media; storage to movement within the same medium.
OPERATION, VARIABLE-CYCLE
computer action in which any cycle of action or operation may be of different lengths. This kind of action takes place in an asynchronous computer.
OPERATOR
the person who actually manipulates the computer controls, places information media into the input devices, removes the output, presses the start button, etc.; a mathematical symbol which represents a mathematical process to be performed on an associated function; generally, the quantity which indicates an operation to be performed upon an operand e.g. ???? , ???? etc-).
OR-CIRCUIT
an electrical or mechanical device which will yield an output signal whenever there are one or more inputs on a multichannel input, e.g. an OR gate is one in which a pulse output occurs whenever one or more inputs are pulsed; forward merging of pulses slimiltaneously providing reverse isolation. See Inclusive- OR and Exclusive-OR.
ORDER
a defined successive arrangement of elements or events. The word order is losing favor as a synonym for instruction, command or operation part sue to ambiguity.
OR-OPERATOR
a logical operator which has the property such that if P or Q are tow statements, then the statement "P OR Q" is true or false precisely according to the following table of possible combinations: (See Inclusive and Exclusive OR)
```
       P                Q          P or Q
      False   0      True   1     True   1
      True    1      False  0     True   1
      True    1      True   1     True   1
      False   0      False  0     False  0
```
The term disjunction is applied to this operator.
OSCILLATIONS, FREE
oscillating currents or voltages which continue to flow in a tuned circuit after the impressed voltage has been removed. Their frequency is the resonant frequency of the circuit. They are due to interchange electromagnetic and electrostatic energy and the fact that a time rate of change of charge is an electric current which stores energy in the form of a magnetic field and a time rate of change of magnetic field produces a voltage which stores energy in the form of an electric field. The energies of these two fields interchange.
OUTPUT
information transferred from the internal storage of a computer to secondary or external storage; information transferred to any device exterior to the computer.
OUTPUT-BLOCK
a portion of the internal storage reserved primarily for receiving, processing and transmitting data which is to be transferred out.
OVERFLOW
in an arithmetic operation, the generation of a quantity beyond the capacity of the register or location which is to receive the result; over capacity; the information contained in an item of information which is in excess of a given amount.
PACK
to include several brief or minor items of information into one machine item or word by utilizing different sets of digits for the specification of each brief or minor item.
PARALLEL
handled simultaneously in separate facilities; operating on two or more parts of a word or item simultaneously; contrasted with serial.
PARAMETER
in a subroutine, a quantity which may be given different values when the subroutine is used in different main routines or in different parts of one main routine, but which usually remains unchanged throughout any one such use; in a generator, a quantity used to specify input-output devices, to designate subroutines to be included, or otherwise to describe the desired routine to be generated; in mathematics, a variable which can be held constant temporarily, usually giving rise to a family of curves.

BRL 1961, GLOSSARY, start page 1106

PARAMETER, PRESET
a parameter incorporated into a subroutine during input.
PARAMETER, PROGRAM
a parameter incorporated into a subroutine during computation. A program parameter frequently comprises a word stored relative to either the subroutine or the entry point and dealt with by the subroutine during each reference. It may be altered by the routine and/or may vary from one point of entry to another.
PATCH
section of coding inserted into a routine to correct a mistake or alter the routine; explicitly transferring control from a routine to a section of coding and back again.
PENTODE
a five-electrode vacuum tube containing a cathode, control grid, screen grid, suppressor grid, and plate. The grids may be referred to as grids no. 1, 2, and 3, respectively.
PERFORATION, RATE of
number of characters, rows or words punched in a paper tape by a device per unit of time.
PHOSPHORESCENCE
the property of emitting light for some time after excitation.
PIEZOELECTRIC
the effect of producing a voltage by placing a stress variation, either by compression, by expansion, or by twisting, on a material, usually certain crystals and, conversely, the effect of producing a stress in a crystal by applying a voltage to it.
PLOTTING-BOARD
a device capable of graphically presenting information, usually as curves of one or more variables; analogue curve or point tracer.
PLUG-BOARD
a removable panel containing an ordered array of terminals which may be interconnected by short electrical leads according to a prescribed pattern and hence designating a specific program or machine step. The entire panel, pre-wired, may be inserted for different programs. Used to a large extent in CPC's, printers, tabulators, summary punches and some computers e.g. the Univac File Computer.
POINT
the dot that marks the separation between the integral and fractional parts of a quantity; i.e., between the coefficients of the zero and the minus one powers of the number base. It is usually called, for a number system using base two, a binary point; for base ten, a decimal point, etc; base point; radix.
POST MORTEM
a routine which, either automatically or on demand, prints information concerning the contents of the registers and storage locations at the time the routine stopped, in rder to assist in the location of a mistake in coding.
POTENTIOMETER
a variable voltage divider, a resistor which has a variable contact arm so that any portion of the potential applied between its ends may be selected.
PRECISION
the degree of exactness with which a quantity is stated; a relative term often based on the number of significant digits in a measurement. See also Accuracy.
PRECISION, DOUBLE
retention of twice as many digits of a quantity as the computer normally handles, e.g. a computer whose basic word consists of 10 decimal digits is called upon to handle 20 decimal digit quantities. PRE-STORE to set an initial value for the address of an operand or a cycle index; to restore; to store a quantity in an available or convenient location before it is required in a routine.
PROGRAM
a plan for the solution of a problem. A complete program includes plans for the transcription of data, coding for the computer and plans for the absorption of the results into the system. The list of coded instructions is called a routine; to plan a computation or process from the asking of a question to the delivery of the results, including the integration of the operation into an existing system. Thus programming consists of planning and coding, including numerical analysis, systems analysis, specification of printing formats, and any other functions necessary to the integration of a computer in a system.
PROGRAM, ASSEMBLY
a program designed to place various sections of another program in their programer designated locations. Some assembly programs also contain the elements of a translator or translation.program.
PROGRAM SENSITIVE MALFUNCTION
a malfunction which occurs only when some unusual combination of program steps occur.
PROGRAMMER
a person who prepares instruction sequences without necessarily converting them into the detailed codes of a particular computer.

BRL 1961, GLOSSARY, start page 1107

PROGRAMMING AUTOMATIC
any technique in which the computer is used to help plan as well as to help code a problem; e.g. compiling routines, interpretive routines.
PROGRAMMING, OPTIMUM
improper terminology for minimal latency coding, i.e., for producing a minimal latency routine; pro- gramming in order to make efficient use of hardware e.g. least storage usage, time share of peripheral equipment, use of time between operations, etc.
PROGRAMMING, RANDOM-ACCESS
programming without regard for the time required for access to the storage positions called for in the program; contrast with minimum access program- ming or minimal latency programming.
PSEUDO-CODE
an arbitrary code, independent of the hardware of a computer, which must be translated into computer code.
PSEUDO-RANDOM
having the property of satisfying one or more of the standard criteria for statistical randomness but being produced by a definite calculation process.
PULSE
a change in the intensity or level of some medium, usually over a relatively short period of time, e.g. a shift in electric potential of a point for a short period of time compared to the time period, i.e., if the voltage level of a point shifts from -10 to +20 volts with respect to ground for a period of 2 microseconds, one says that the point received a 30 volt 2 microsecond pulse.
PULSE-CODE
sets of pulses to which particular meanings have been assigned; the binary representations of characters.
PUNCH, CALCULATING, ELECTRONIC
a card handling machine which reads a punched card, performs a number of sequential operations and punches the result on a card.
PUNCH, CARD
a device which perforates or places holes in cards in specific locations designated by a program.
PUNCH-POSITION
the location of the row in a columniated card e.g. in an 80-column card the rows or "punch position" may be 0 to 9 and "X" and "Y" corres- ponding to position 11 and 12.
PUNCH, SUMMARY
a card handling machine which may be electri- cally connected to another machine, e.g. tabulator and which will punch out on a card the information produced, calculated or summarized by the other machine.
PUNCHING, RATE of
number of cards, characters, blocks, fields or words of information placed in the form of holes distribution on cards, or tape per unit of time.
QUANTITY
a positive or negative real number in the mathe- matical sense. The term quantity is preferred to the term number in referring to numerical data; the term number is used in the sense of natural number and reserved for "the number of digits", the "number of operations", etc.
QUANTITY, DOUBLE-PRECISION
a quantity having twice as many digits as are normally carried in a specific computer.
RANDOM-ACCESS
access to storage under conditions in which the next position from which information is to be obtained is in no way dependent on the previous one.
RANGE
all the values which a function may have; the difference between the limits imposed upon a variable.
RATIO, OPERATING
the ratio obtained by dividing the number of hours of correct machine operation by the total hours of scheduled operation, e.g. on a 168 hour week scheduled operation, if 12 hours of preven- tive maintenance is required and 4.8 hours of un- scheduled dawn time occurs, then the operating ratio is (168 - 16.8)168, which is equivalent to a 90,% operating ratio.
READ
to copy, usually. from one form of storage to another, particularly from external or secondary storage to internal storage; to sense the meaning or arrangements of hardware; to sense the presence of information on a recording medium.
READ-AROUND-RATIO
in electrostatic storage tubes, the number of times a specific spot (digit or location) may be consulted before "spill over" will cause a loss of information stored in surrounding spots, immediate- ly prior to which the surrounding information must be restored; read-around number.
READER, CARD
a mechanism that permits the sensing of infor- mation punched on cards by means of wire brushes, metal feelers, or a photoelectric device, convert- ing the information into electrical pulses that are sensible to the computing system.

BRL 1961, GLOSSARY, start page 1108

READER, TAPE, MAGNETIC
a device capable of restoring to a train or sequence of electrical pulses, information recorded on a magnetic tape in the form of a series of magnetized spots, usually for the purpose of transferring the information to some other storage medium.
READER, TAPE, PAPER
a device capable of restoring to a train or. sequence of electrical pulses, information punched on a paper tape in the form of a series of holes, usually for the purpose of transferring the infor- _ mation to some other storage medium.
READING, RATE of
number of characters, words, fields, blocks or cards sensed by an input sensing device per unit of time. REAL-
TIME
the performance of a computation during the actual time that the related physical process transpires in order that results of the computations are useful in guiding the physical process.
RECORD
a listing of information, usually in printed or printable form; one output of a compiler consisting of a list of the operations and their positions in the final specific routine and containing information describing the segmentation and storage allocation of the routine; to copy or set down information in reusable form for future reference; to make a transcription of data by a systematic alteration of the condition, property or configuration of a physical medium, e.g., placing information on magnetic tape or a drum by means of magnetized spots.
REGENERATION
the process of returning a part of the output signal of an amplifier to its input circuit in such a manner that it reinforces the grid excitation and thereby increases the total amplification; periodic restoration of stored information.
REGISTER
the hardware for storing one or more computer words. Registers are usually nearby zero-access storage devices.
REGISTER, CIRCULATING or MEMORY
a register (or memory) consisting of a means for delaying information and a means for regenerating and reinserting the information into the delaying means.
REGISTER, CONTROL
the accumulator, register or storage unit which stores the current instruction governing a computer operation; an instruction register.
REGISTER, PROGRAM
a register in the control unit which stores the current instruction of the program and controls computer operation during the execution of the instruction; control register; program counter.
REGULATION, VOLTAGE
a measure of the degree to which an. electrical power source maintains its output-voltage stability under varying load conditions.
REPETITION, RATE of PULSE
the number of electric pulses per unit of time experienced by a point in a computer, usually the maximum, normal, or standard rate of pulses.
REPRESENTATIVE-CALCULATING-TIME
a method of evaluating the speed performance of a computer. One method is to use one-tenth of the time required to perform nine complete additions and one complete multiplication. A complete addition or a complete multiplication time includes the time required to procure two operands from high speed storage, perform the operation, and store the result and the time required to select and execute the required number of instructions to do this.
RERUN
to repeat all or part of a program on a computer.
RERUN-POINT
that stage of a computer run at which all information pertinent to the running of the routine is available either to the routine itself or to a rerun routine in order that a run may be reconstituted.
RESET
to return a device to zero or to an initial or arbitrarily selected condition.
RESOLVER
a device which separates or breaks up a quantity, particularly a vector, into constituent parts or elements, e.g. to form the three mutually perpendicular components of a space vector.
RESPONSE, FREQUENCY
a measure of the ability of a device to take into account, follow or act upon a rapidly varying condition, e.g. as applied to amplifiers, the frequency at which the gain has fallen to the one=half power point or to 0.707 of the voltage gain factor; as applied to a mechanical controller, the maxim rate at which changes in condition can be followed and acted upon.

BRL 1961, GLOSSARY, start page 1109

RESTORE
to return a cycle index, a variable address, or other computer word to its initial or preselected value; periodic regeneration of charge, especially in volatile, condenser-action storage systems; when sensing the contents of a storage location destructively, to return the contents or regenerate the contents after reading.
RETURN
to go back to a specific, planned point in a program, usually when an error is detected, for the purpose of rerunning the program. -Rerun points are usually three to five minutes apart to avoid long periods of lost computer time. Information pertinent to a rerun is available in standby registers from point to point.
REWIND
to return a film or magnetic tape to its beginning or passed location.
ROLLBACK
equivalent to rerun when referring to tapesequenced computers; to recapture tape-inscribed data.
ROLL-OUT
to read a register or counter by adding ones to the respective digits simultaneously obtaining a signal as each column returns to zero, until all columns have returned to zero, usually requiring n additions, where n is the number base.
ROUND-OFF
to change a more precise quantity to a less precise one, according to some rule, usually in order to keep the number of digits expressing the number.
ROUTINE
a set of coded instructions arranged in proper sequence to direct the computer to perform a desired operation or series of operations.
ROUTINE, COMPILING
an executive routine which, before the desired computation is started, translates a program expressed in pseudo-code into machine code (or into another pseudo-code for further translation by an interpreter). In accomplishing the translation, the compiler is required to decode, convert, select, generate, allocate, adapt, orient, incorporate, or record.
ROUTINE, DIAGNOSTIC
a specific routine designed to locate either a malfunction in the computer or a mistake in coding.
ROUTINE, EXECUTIVE
a set of coded instructions designed to process and control other sets of coded instructions; a set of coded instructions used in realizing "automatic coding"; a master set of coded instructions.
ROUTINE, FLOATING-POINT
a set of coded instructions arranged in proper sequence to direct the computer to perform a specific set of operations which will permit floating-point operation, e.g. enable the use of a fixedpoint machine to handle information on a floatingpoint basis from an external point of view. Floating- point routines are usually used in computers which do not have built in floating-point circuitry, in which case floating-point operation must be programmed.
ROUTINE, GENERAL
a routine expressed in computer coding designed to solve a class of problems, specializing to a specific problem when appropriate parametric values are supplied.
ROUTINE, INTERPRETIVE
an executive routine which, as the computation progresses, translates a stored program expressed in some machine-like pseudo-code into machine code and performs the indicated operations, by means of subroutines as they are translated. An interpretive routine is essentially a closed subroutine which operates successively on an indefinitely-long sequence of program parameters (the pseudo-instructions and operands). It may usually be entered as a closed subroutine and exitted by a pseudo-code exit instruction.
ROUTINE, MINIMAL LATENCY
especially in reference to serial storage systems, a routine so coded, by ,judicious arrangement of data and instructions in storage, that the actual latency is appreciably less than the expected random-access latency.
ROUTINE, RERUN
a routine designed to be used in the wake of a computer malfunction or a coding or operating mistake to reconstitute a routine from the last previous rerun point; roll back routine. See Rerun.
ROUTINE, SEQUENCE-CHECKING
a routine which checks every instruction executed, printing certain data, e.g., to print out the coded instruction with addresses, and the contents of each of several registers, or it may be designed to print out only selected data, such as transfer instructions and the quantity actually transferred.
ROUTINE, SERVICE
a routine designed to assist in the actual operation of the computer. Tape comparison, block location, certain post mortems, and correction routines fall in this class.

BRL 1961, GLOSSARY, start page 1110

ROUTINE, SPECIFIC
a routine expressed in computer coding designed to solve a particular mathematical, logical, or data-handling problem in which each address refers to explicitly stated registers and locations.
ROUTINE, TEST
a routine designed to show whether a computer is functioning properly or not.
RUN
one performance of a program on a computer; performance of one routine, or several routines automatically linked so that they form an operating unit, during which manual manipulations are not required of the computer operator.
SCALE
to alter the units in which all variables are expressed so as to bring all magnitudes within the capacity of the computer or routine at hand.
SCANNER
an instrument which automatically samples or interrogates the state of various processes, conditions, or physical states and initiates action in accordance with the information obtained.
SEGMENT
to divide a routine in parts each consisting of an integral number of subroutines, each part capable of being completely stored in the internal storage and containing the necessary instructions to ,jump to other segments; in a routine too long to fit in- to internal storage, a part short enough to be stored entirely in the internal storage and contain- ing the coding necessary to call in and jump auto- matically to other segments. Routines which exceed internal storage capacity may be automatically divided into segments by a compiler.
SELECT
to take the alternative A if the report on a condition is of one state, and alternative B if the report on the condition is of another state; to choose a needed subroutine from a file of sub- routines.
SELECTOR
a device which interrogates a condition and initiates a particular operation according to the interrogation report.
SENSE
to examine, particularly relative to a criterion; to determine the present arrangement of some element of hardware, especially a manually-set switch; to read holes punched in paper.
SENTINEL
a symbol marking the beginning or the end of some element of information such as a field, item, block, tape, etc; a tag.
SEQUENCE, PSEUDO-RANDOM
an order of numbers produced by a definite recursive rule but satisfying one or more of the standard tests for randomness.
SEQUENCER
a machine which puts items of information into a particular order, e.g., it will determine whether A is greater than, equal to, or less than B, and sort or order accordingly.
SERIAL
handle one after the other in a single facility, such as transfer or store in a digit by digit time sequence.
SERVOMECHANISM
a closed loop system in which the error or deviation from a desired or pre-set norm is reduced to zero, and one in which mechanical position is usually the controlled variable, e.g., a synchro- nized drum storage system requires a servomechanism to insure synchronism between a crystal controlled electronic oscillator and a rotating cylinder; an AA fire control gun-positioning system requires a servo to insure that deviations are corrected.
SHIFT
to move the characters of a unit of information column-wise right or left. For a number, this is equivalent to multiplying or dividing by a power of the base of notation.
SHIFT, ARITHMETIC
to multiply or divide a quantity by a power of the number base, e.g. binary 1011 represents deci- mal 11, therefore two arithmetic shifts to the left is binary 101100, which represents decimal 44; which means 11 was multiplied by two twice when a binary number is shifted. If the decimal 11 was shifted twice, it would mean multiplication by 100, or a result of 1100.
SHUT, CYCLIC
a shift in which the digits dropped off at one end of a word are returned at the other in a circular fashion; logical, non-arithmetical or circular shift.
SIGNIFICANCE
the arbitrary rank, priority, or order of rela- tive magnitude assigned to a given position or column in a number; the significant digits of a number are a set of digits, usually from consecutive columns beginning with the most significant digit different from zero and ending with the least significant digit whose value is known are assumed relevant, e.g., 2300.0 has five significant digits, whereas 2300 probably has two significant digits. However 2301 has four significant digits.

BRL 1961, GLOSSARY, start page 1111

SIMULATION
the representation of physical systems and phenomenons by computers, models or other equipment.
SKIP
an instruction to proceed to the next instruction; a "blank" instruction.
SOLVER, EQUATION
a calculating device, usually analog, which arrives at the solution to systems of linear simultaneous non-differential equations or determine the roots of polynomials or both.
SORT
to arrange items of information according to rules dependent upon a key or field contained in the items.
STACKER, CARD
a mechanism that accumulates cards in a bin after they have passed through a machine operation. STANDARDIZE to adjust the exponent and mantissa of a floating-point result so that the mantissa lies in the prescribed normal range; normalize; see Floatingpoint Representation.
STORAGE
preferred to memory, any device into which units of information can be copies, which will hold this information, and from which the information can be obtained at a later time; devices, such as plugboards, which hold information in the form of arrangements of physical elements, hardware, or equipment; the erasable storage in any given computer.
STORAGE, BUFFER
a synchronizing element between two different forms of storage, usually between internal and external; an input device in which information is assembled from external or secondary storage and stored ready for transfer to internal storage; an output device into which information is copied from internal storage and held for transfer to secondary or external storage. Computation continues while transfers between buffer storage and secondary or internal storage or vice versa take place.
STORAGE, CIRCULATING
a device using a delay line, or unit which stores information in a train or pattern of pulses, where the pattern of pulses issuing at the final end are sensed, amplified, reshaped and re-inserted in the delay line at the beginning end. See DelayLine.
STORAGE, DYNAMIC
storage such that information at a certain position is moving or varying with time and so is not always available instantly; e.g., acoustic delay line, magnetic drum; circulating or re-circulating of information in a medium.
STORAGE, ELECTROSTATIC
a device possessing the capability of storing changeable information in the form of charged or uncharged areas on the screen of a cathode ray tube.
STORAGE, ERASABLE
media which may hold information that can be changed; i.e., the media can be re-used; e.g., magnetic tape, drum, or core.
STORAGE, EXTERNAL
storage facilities divorced from the computer itself but holding information in the form prescribed for the computer; e.g., magnetic tapes, magnetic wire, punched cards, etc.
STORAGE, INTERNAL
storage facilities forming an integral physical part of the computer and directly controlled by the computer; the total storage automatically accessible to the computer.
STORAGE, MAGNETIC
any storage system which utilizes the magnetic properties of materials to store information.
STORAGE, MERCURY
columns of a liquid mercury medium used as a storage element by the delaying action or time of travel of sonic pulses which are circulated by having electrical amplifier, shaper, and timer circuits complete the loop.
STORAGE, NON-ERASABLE
media used for containing information which cannot be erased and reused, such as punched paper tapes, and punched cards.
STORAGE, NON-VOLATILE
storage media which retain information in the absence of power and which may be made available upon restoration of power; e.g., magnetic tapes, drums, or cores.
STORAGE, PARALLEL
storage in which all bits, or characters, or (especially) words are essentially equally available in space, without time being one of the coordinates. Parallel storage contrasts with serial storage. When words are in parallel, the storage is said to be parallel by words; when characters within words (or binary digits within words or characters) are dealt with simultaneously, not one after the other, the storage is parallel by characters (or parallel by bit respectively . Contrasted with Storage, Parallel.

BRL 1961, GLOSSARY, start page 1112

STORAGE, SECONDARY
storage facilities not an integral part of the computer but directly connected to and controlled by the computer; e.g., magnetic drum, magnetic tapes, etc.
STORAGE, SERIAL
storage in which time is one of the coordinates used to locate any given bit, character, or (especially) word. Storage in which words, within given groups of several words, appear one after the other in time sequence, and in which access time therefore includes a variable latency or waiting time of from zero to many-times, is said to be serial by word. Storage in which the individual bits comprising a word appear in time sequence is serial by bit. Storage for coded-decimal or other non- binary numbers in which the characters appear in time sequence is serial by character; e.g., magnetic drums are usually serial by word but may be serial by bit, or parallel by bit, or serial by character and parallel by bit, etc.
STORAGE, STATIC
storage such that information is fixed in space and available at any time; e.g., flip-flop, electrostatic, or coincident-current magnetic-core storage.
STORAGE, TEMPORARY
internal storage locations reserved for intermediate and partial results.
STORAGE, VOLATILE
storage media such that if the applied power is cut off, the stored information is lost; e.g., acoustic delay lines, electrostatic tubes.
STORAGE, WORKING
a portion of the internal storage reserved for the data upon which operations are being performed.
STORAGE, ZERO-ACCESS
storage for which the latency (waiting time) is small at all times.
STORE
to transfer an element of information to a device from which the unaltered information can be obtained at a later time.
SUBROUTINE
the set of instructions necessary to direct the computer to carry out a well defined mathematical or logical operation; a subunit of a routine. A subroutine is often written in relative or symbolic coding even when the routine to which it belongs is not.
SUBROUTINE, CLOSED
a subroutine not stored in its proper place in the linear operational sequence, but stored away from the routine which refers to it. Such a subroutine is entered by a ,jump, and provision is made to return, i.e., to jump back to the proper point in the main routine at the end of the subroutine.
SUBROUTINE, DYNAMIC
a subroutine which involves parameters, such as decimal point position or item size, from which a relatively coded subroutine is derived: The computer itself is expected to adjust or generate the subroutine according to the parametric values chosen.
SUBROUTINE, OPEN
a subroutine inserted directly into the linear operational sequence, not entered by a jump. Such a subroutine must be recopied at each point that it is needed in a routine. SUBROUTINE, STATIC
a subroutine which involves no parameters other than the addresses of the operands.
SUBSTITUTE
to replace an element of information by some other element of information.
SWITCH, ELECTRONIC
a circuit which causes a start-and-stop action or a switching action by electronic means.
SWITCH, FUNCTION
a circuit having a fixed number of inputs and outputs designed such that the output information is a function of the input information, each expressed in a certain code or signal configuration or pattern.
SYMBOL, LOGICAL
a symbol used to represent a logical element graphically.
SYSTEM
an assembly of components united by some form of regulated interaction; an organized whole.
TABULATOR
a machine which reads information from one medium, e.g., cards, paper tape, magnetic tape, etc. and produces lists, tables, and totals on separate forms or continuous paper.
TAG
a unit of information, whose composition differs from that of other members of the set so that it can be used as a marker or label; a sentinel.

BRL 1961, GLOSSARY, start page 1113

TANK
a unit of acoustic delay line storage, containing a set of channels each forming a separate recirculation path; a circuit consisting of inductance and capacitance used for the purpose of sustaining electrical oscillations.
TAPE, MAGNETIC
a tape or ribbon of any material impregnated or coated with magnetic material on which information may be placed in the form of magnetically polarized spots.
TAPE, PROGRAM
a tape which contains the sequence of instructions required for solving a problem and which may be read by the computer.
TERNARY
pertaining to the system of notation utilizing the base of 3, employing the characters 0, 1, and 2.
TEST, CRIPPLED-LEAP-FROG
a variation of the leap-frog test, modified so that it repeats its tests from a single set of storage locations rather than a changing set of locations.
TEST, LEAPFROG
a program designed to discover computer malfunction, characterized by the property that it performs a series of arithmetical or logical operations on one group of storage locations, transfers itself to another group of storage locations, checks the correctness of the transfer, then begins the series of operations over again. Eventually, all storage positions will have been occupied and the test will be repeated.
TETRAD
a group of four, usually four pulses, in particular, a group of four pulses used to express a decimal digit, or a sexadecimal digit by means of four (binary) pulses.
TETRODE
a four-electrode vacuum tube containing a cathode, control grid, screen grid, and plate.
THERMISTOR
the thermistor is a solid state, semiconducting device made by sintering mixtures of the oxide powders of various metals. It is made in many shapes, such as beads, disks, flakes, washers, and rods, to which contact wires are attached. As its temperature is changed, the electrical resistance of the thermistor varies. The associated temperature coefficient of resistance is extremely high, nonlinear, and negative.
THERMOCOUPLE
a device made up of two bi-metal joints (usually wires forming a closed loop) having the property that if the two ,junctions are maintained at different temperatures, a difference of potential is brought into existence equally distributed between the two junctions.
THREE-ADDRESS
see Code, Multiple-address.
THYRATRON
a hot-cathode, gas-discharge tube in which one or more electrodes are used to control electrostatically the starting of an unidirectional flow of current. TIME, CODE CHECKING
all time spent checking out a problem on the machine making sure that the problem is set up correctly, and that the code is correct.
TIME, ENGINEERING or SERVICING
all machine down time necessary for routine testing (good or bad), for machine servicing due to breakdowns, or for preventive servicing measures, e.g., block tube changes. Includes all test time (good or bad) following breakdown and subsequent repair or preventive servicing.
TIME, IDLE
time in which machine is believed to be in good operating condition and attended by service engineers but not in use on problems. To verify that the machine is in good operating condition, nachine tests of the leapfrog variety may be run.
TIME, NO CHARGE MACHINE-FAULT
unproductive time due to a computer fault such as the following: (1) non-duplication, (2) transcribing error, (3) input-output malfunction, (4) machine malfunction resulting in an incomplete run.
TIME, NO CHARGE NON-NACHINE-FAULT
unproductive time due to no fault of the computer such as the following: (1) good duplication, (2) error in preparation of input data, (3) error in arranging the program deck, (4) error in operating instructions or misinterpretation of instructions, (5) unscheduled good testing time, run during normal production period when machine malfunction is suspected but is demonstrated not to exist.
TIME, PRODUCTION
good computing time, including occasional duplication of one case for a check or rerunning of the test run. Also, duplication requested by the sponsor; any reruns caused by misinformation or bad data supplied by sponsor. Error studies using different intervals, convergence criteria, etc.

BRL 1961, GLOSSARY, start page 1114

TIME, STANDBY UNATTENDED
time in which the machine is in an unknown condition and not in use of problems. Includes time in which machine is known to be defective and work is not being done to restore it to operating condition. Includes breakdowns which render it unavailable due to outside conditions (power outages, etc.).
TIME, SYSTEM, IMPROVEMENT all machine down time needed for the installation and testing of new components, large or small, and machine down time necessary for modification of existing components. Includes all programmed tests following the above actions to prove machine is operating properly.
TRACK
in a serial magnetic storage element, a single path containing a set of pulses.
TRANSCRIBE
to copy, with or without translating, from one external storage medium to another.
TRANSDUCER
a device which converts energy from one form to another, e.g., a quartz crystal imbedded in mercury can change electrical energy to sound energy as is done in sonic delay lines in computer storage systems.
TRANSFER
to copy, exchange, read, record, store, transmit, transport, or write data; to change control; to jump to another location.
TRANSFER, CONDITIONALLY
to copy, exchange, read, record, store, transmit, or write data or to change control or ,jump to another location according to a certain specified rule or in accordance with a certain criterion.
TRANSFER, PARALLEL
a system of data transfer in which the characters of an element of information are transferred simultaneously over a set of paths.
TRANSFER, SERIAL
a system of data transfer in which the characters of an element of information are transferred in sequence over a single path in consecutive time positions.
TRANSFER, UNCONDITIONAL
an instruction which causes the subsequent instruction to be taken from an address which is not the next one in the sequence in a digital computer which ordinarily obtains its instructions serially from an ordered sequence at all other times.
TRANSFORM
to change information in structure or composition without altering the meaning or value; to normalize, edit, or substitute.
TRANSIENT
a phenomenon experiencing a change as a function of time; something which is temporary; a build-up or breakdown in the intensity of a phenonenon until a steady state condition is reached; an aperiodic phenomenon; the time rate of change of energy is finite and some form of energy storage is usually involved.
TRANSISTOR
an electronic device utilizing semi-conductor properties to control the flow of currents from one source in one circuit by currents from another circuit, e.g. a triod transistor permits the control of current in one circuit by the use of a smaller current in another circuit, with the transistor common to both circuits.
TRANSLATE
to change inforamtion (e.g., problem statements in pseudo-code, data, or coding) from one language to another without significantly affecting the meaning.
TRANSMIT
to reproduce information in a new location replacing whatever was previously stored and clearing or erasing the source of the information.
TRANSPORT
to convey as a whole from one storage device to another.
TROUBLE-SHOOT
to search for a coding mistake or the cause of a computer malfunction in order to remove same.
TRUNCATE
to drop digits of a number of terms of a series thus lessening precision, e.g. the number 3.14159265 is truncated to five figures in 3.1415, whereas one may round off to 3.1416.
TRUNK
a path over which information is transferred; a bus.
TUBE, ACORN
a small vacuum tube designed for ultra-highfrequency circuits. The tube has short electron transit time and low interelectrode capacity.

BRL 1961, GLOSSARY, start page 1115

TUBE, CATHODE-RAY
an electronic vacuum tube containing a screen on which information may be stored by means of a multigrid modulated beam of electrons from the thermionic emitter, storage effected by means of charged or uncharged spots; a storage tube; a Williams tube; an oscilloscope tube; a picture tube.
TUBE, WILLIAMS
a cathode ray tube used as an electrostatic storage device of the type designed by F. C. Williams, University of Manchester, England.
TWO-ADDRESS
see Code, Multiple-address.
TYPEWRITER, ELECTRIC
a hand operated electric powered individual character printing device having the property that almost every operation of the machine after the keys are touched by human fingers is performed by electric power instead of manual power; a typewriter powered by electricity, in all other respects the same as a manually powered typewriter.
ULTRASONICS
the field of science devoted to frequencies of sound above the human audio range, i.e. above 20 kilocycles per second.
UNCONDITIONAL
not subject to conditions external to the specific instruction.
UNDERFLOW
the condition which arises when a machine computation yields a result which is smaller than the smallest possible quantity which the machine is capable of storing; in floating- point operations, when the exponent plus the excess becomes negative.
UNPACK
to decompose packed information into a sequence of separate words or elements.
UNWIND
to code explicitly, at length and in full all the operations of a cycle thus eliminating all red-tape operations in the final problem coding. Unwinding may be performed automatically by the computer during assembly, generation, or compilation.
VALIDITY
correctness; especially the degree of the closeness by which iterated results approach the correct result.
VARISTOR
a passive resistor-like circuit element whose resistance is a function of the current through it or voltage across its terminals, i.e. the current through it is a non-linear function of the voltage across its terminals, hence the linear form of Ohms Law is not obeyed; a self-varying resistance.
VERIFIER
a device on which a manual transcription can be verified by comparing a retranscription with it character- by-character as it is being retranscribed.
VERIFY
to check a data transfer or transcription, especially those involving manual processes.
WIRE, MAGNETIC
wire made of a magnetic material along small incremental lengths of which magnetic dipoles are placed in accordance with binary information.
WORD
a set of characters which occupies one storage location and is treated by the computer circuits as a unit and transported as such. Ordinarily a word is treated by the control unit as an instruction, and by the arithmetic unit as a quantity. Word lengths are fixed or variable depending on the particular computer.
WORD, INFORMATION
an ordered set of characters bearing at least one meaning and handled by a computer as a unit, including separating spacing, which may be contrasted with instruction words.
WORD-TIME
especially in reference to words stored serially, the time required to transport one word from one storage device to another. See also Access Time.
WRITE
to transfer information to an output medium; to copy, usually from internal storage to external storage; to record information in a register, location, or other storage device or medium.
ZERO
nothing; positive binary zero is usually indicated by the absence of digits or pulses in a word; negative binary zero in a computer operating on ones complements by a pulse in every pulse position in a word; in a coded decimal machine, decimal zero and binary zero may not have the same representation. In most computers, there exist distinct and valid representation both for plus and for minus zero.

BRL 1961, GLOSSARY, start page 1116

ZERO-SUPPRESSION
the editing or elimination of non-significant zeros to the left of the integral part of a quantity before printing operations are initiated; a part of editing.
ZONE
a portion of internal storage allocated for a particular function or purpose; any of the three top positions of 12, 11 and 0 on a punch card. In these zone positions, a second punch can be in- serted so that with punches in the remaining positions 1 to 9, alphabetic characters may be represented.

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CHAPTER IV BIBLIOGRAPHY

CHAPTER V GLOSSARY OF COMPUTER ENGINEERING AND PROGRAMMING TERMONOLOGY (REVISED)

CHAPTER IV
BIBLIOGRAPHY

CHAPTER V
GLOSSARY OF COMPUTER ENGINEERING AND PROGRAMMING TERMONOLOGY
(REVISED)