1. Abstraction A model of a complex system thatincludes only the details essential to theviewer

61. Access Time The time it takes for a block to start beingread; the sum of seek time and latency

46. Adder An electronic circuit that performs anaddition operation on binary values

62. Addressability The number of bits stored in eachaddressable location in memory

84. Algorithm Unambiguous instructions for solving aproblem or subproblem in a finite amountof time using a finite amount of data

16. Analog Data A continuous representation of data

63. Arithmetic/LogicUnit (ALU)

The computer component that performsarithmetic operations (addition,subtraction, multiplication, division) andlogical operations (comparison of twovalues)

85. Assembler A program that translates an assembly-language program into machine code

86. AssemblerDirectives

Instructions to the translating program

87. AssemblyLanguage

A low-level programming language inwhich a mnemonic represents each of themachine-language instructions for aparticular computer

17. Bandwidth The number of bits or bytes that can betransmitted from one place to another ina fixed amount of time

5. Base The foundational value of a numbersystem, which dictates the number ofdigits and the value of digit positions

6. Binary Digit A digit in the binary number system; a 0or a 1

7. Bit Binary digit

64. Block The information stored in a sector

47. Boolean Algebra A mathematical notation for expressingtwo-valued logical functions

88. BooleanExpression

A sequence of identifiers, separated bycompatible operators, that evaluates toeither true or false

65. Bus width The number of bits that can betransferred in parallel over the bus

8. Byte Eight binary digits

66. Cache Memory A type of small, high-speed memory usedto hold frequently used data

18. Character Set A list of the characters and the codes used torepresent each one

48. Circuit A combination of interacting gates designedto accomplish a specific logical function

49. CircuitEquivalence

The same output for each correspondinginput-value combination for two circuits

89. Code-Coverage(clear-box)testing

Testing a program or subprogram based oncovering all the statements in the code

50. CombinationalCircuit

A circuit whose output is solely determinedby its input values

90. Comment Explanatory text for the human reader

19. CompressionRatio

The size of the compressed data divided bythe size of the uncompressed data

2. ComputerHardware

The physical elements of a computingsystem

3. ComputerSoftware

The programs that provide the instructionsthat a computer executes

4. ComputingSystem

Computer hardware, software, and data,which interact to solve problems

67. Control Unit The computer component that controls theactions of the other components so as toexecute instructions in sequence

68. CPU The central processing unit, a combinationof the arithmetic/logic unit and the controlunit; the 'brain' of a computer that interpretsand executes instructions

69. Cylinder The set of concentric tracks on all surfaces

20. Data Basic values or facts

21. DataCompression

Reducing the amount of space needed tostore a piece of data

91. Data Coverage(black-box)testing

Testing a program or subprogram based onthe possible input values, treating the codeas a black box

92. Desk Checking Tracing the execution of a design on paper

22. Digital Data A discrete representation of data

23. Digitize The act of breaking information down intodiscrete pieces

24. Floating Point A representation of a real number that keepstrack of the sign, mantissa, and exponent

51. Full adder A circuit that computes the sum of two bits,taking an input carry bit into account

52. Gate A device that performs a basic operation onelectrical signals, accepting one or moreinput signals and producing a single outputsignal

Computer Science Illuminated Fifth Edition - Vocab Chap1-6Study online at quizlet.com/_ins21

53. Half Adder A circuit that computes the sum of two bitsand produces the appropriate carry bit

25. HuffmanEncoding

Using a variable-length binary string torepresent a character so that frequently usedcharacters have short codes

26. Information Data that has been organized or processed ina useful manner

70. Input Unit A device that accepts data to be stored inmemory

71. InstructionRegister (IR)

The register that contains the instructioncurrently being executed

9. Integer A natural number, a negative of a naturalnumber, or zero

54. IntegratedCircuit(chip)

A piece of silicon on which multiple gateshave been embedded

27. KeywordEncoding

Replacing a frequently used word with asingle character

72. Latency The time it takes for the specified sector to bein position under the read/write head

93. Loader A piece of software that takes a machine-language program and places it into memory

55. LogicDiagram

A graphical representation of a circuit; eachtype of gate has its own symbol

28. LosslessCompression

A data compression technique in which thereis no loss of information

29. LossyCompression

A data compression technique in which thereis loss of information

94. MachineLanguage

The language made up of binary-codedinstructions that is used directly by thecomputer

73. Motherboard The main circuit board of a personal computer

30. Multimedia Several different media types

56. Multiplexer A circuit that uses a few input control signalsto determine which of several input data linesis routed to its output

10. NaturalNumber

The number 0 and any number obtained byrepeatedly adding 1 to it

11. NegativeNumber

A value less than 0, with a sign opposite to itspositive counterpart

12. Number A unit of an abstract mathematical systemsubject to the laws of arithmetic

74. Output Unit A device that prints or otherwise displays datastored in memory or makes a permanent copyof information stored in memory or anotherdevice

31. Overflow The condition that occurs when the results ofa calculation are too large to represent in agiven machine

75. Pipelining A technique that breaks an instruction intosmaller steps that can be overlapped

32. Pixels Individual dots used to represent a picture;stands for picture elements

13. PositionalNotation

A system of expressing numbers in whichthe digits are arranged in succession, theposition of each digit has a place value, andthe number is equal to the sum of theproducts of each digit by its place value

76. ProgramCounter (PC)

The register that contains the address of thenext instruction to be executed

95. Pseudocode A language designed to express algorithms

33. Pulse-codeModulation

Variation in a signal that jumps sharplybetween two extremes

34. Radix Point The dot that separates the whole part fromthe fractional part in a real number in anybase

35. Raster-graphicsformat

Storing image information pixel by pixel

14. RationalNumber

An integer or the quotient of two integers(division by zero excluded)

36. Reclock The act of reasserting an original digitalsignal before too much degradation occurs

77. Register A small storage area in the CPU used tostore intermediate values or special data

37. Resolution The number of pixels used to represent apicture

38. Run-lengthEncoding

Replacing a long series of repeatedcharacters with a count of the repetition

39. ScientificNotation

An alternative floating-point representation

78. Sector A section of a track

79. Seek Time The time it takes for the read/write head toget positioned over the specified track

57. Semiconductor Material such as silicon that is neither agood conductor nor a good insulator

58. SequentialCircuit

A circuit whose output is a function of itsinput values and the current state of thecircuit

80. SharedMemoryParallelProcessor

The situation in which multiple processorsshare a global memory

40. Signed-MagnitudeRepresentation

Number representation in which the signrepresents the ordering of the number(negative and positive) and the valuerepresents the magnitude

41. Spatial Compression Movie compression technique based on the same compression techniques used for still images

81. Synchronous Processing Multiple processors apply the same program in lockstep to multiple data sets

42. Temporal Compression Movie compression technique based on differences between consecutive frames

43. Ten's Complement A representation of negative numbers, such that the negative of Iis 10 raised to kminus I

96. Test Plan A document that specifies how a program is to be tested

97. Test Plan Implementation Using the test cases specified in a test plan to verify that a program outputs the predicted results

82. Track A concentric circle on the surface of a disk

83. Transfer Rate The rate at which data moves from the disk to memory

59. Transistor A device that acts either as a wire or a resister, depending on the voltage level of an input signal

60. Truth Table A table showing all possible input values and the associated output values

44. Vector Graphics Representation of an image in terms of lines and shapes

45. Video Codec Methods used to shrink the size of a movie

98. Virtual Computer (machine) A hypothetical machine designed to illustrate important features of a real machine

15. Word A group of one or more bytes; the number of bits in a word is the word length of the computer