Final Terms to Know

Question 1

accessor method

Answer 1

a method that accesses an object but does not change it

Question 2

ACK

Answer 2

in data networking, an acknowledgement (or acknowledgment) is a signal passed between communicating processes or computers to signify acknowledgement, or receipt of response, as part of a communications protocol

Question 3

actual parameter

Answer 3

Formal parameters are the parameters as they are known in the function definition. Actual parameters (also known as arguments) are what are passed by the caller.

Question 4

address

Answer 4

the code that identifies where a piece of information is stored

Question 5

algorithm

Answer 5

an unambiguous, executable, and terminating specification of a way to solve a problem

Question 6

API

Answer 6

(Application Programming Interface) a code library for building programs

Question 7

argument

Answer 7

a value supplied in a method call, or one of the values combined by an operator

Question 8

arithmetic/Logic Unit (ALU)

Answer 8

a digital circuit that performs integer arithmetic and logical operations

Question 9

ARQ Algorithm

Answer 9

Automatic Repeat reQuest (ARQ), also known as Automatic Repeat Query, is an error-control method for data transmission that uses acknowledgements (messages sent by the receiver indicating that it has correctly received a data frame or packet) and timeouts (specified periods of time allowed to elapse before an acknowledgment is to be received) to achieve reliable data transmission over an unreliable service. If the sender does not receive an acknowledgment before the timeout, it usually re-transmits the frame/packet until the sender receives an acknowledgment or exceeds a predefined number of re-transmissions

Question 10

ASCII

Answer 10

the American Standard Code for Information Interchange is a character-encoding scheme originally based on the English alphabet that encodes 128 specified characters - the numbers 0-9, the letters a-z and A-Z, some basic punctuation symbols, some control codes that originated with Teletype machines, and a blank space - into the 7-bit binary integers

Question 11

assembly language

Answer 11

an assembly language is a low-level programming language for a computer, or other programmable device, in which there is a very strong (generally one-to-one) correspondence between the language and the architecture’s machine code instructions

Question 12

binary

Answer 12

number system, also known as base-2, that represents numeric values using two symbols: typically 0 and 1

Question 13

bit

Answer 13

binary digit; the smallest unit of information, having two possible values: 0 and 1. A data element consisting of n bits has 2^n possible values.

Question 14

boolean

Answer 14

a type with two possible values: true and false

Question 15

boolean expression

Answer 15

an expression in a programming language that produces a Boolean value when evaluated, i.e. one of true or false

Question 16

boolean operator

Answer 16

an operator that can be applied to Boolean values. Java has three Boolean operators: &&, ||, and !

Question 17

byte

Answer 17

a number made up of eight bits. Essentially all currently manufactured computers use a byte as the smallest unit of storage in memory.

Question 18

bytecode

Answer 18

instructions for the Java virtual machine

Question 19

cache memory

Answer 19

random access memory (RAM) that a computer microprocessor can access more quickly than it can access regular RAM

Question 20

cast

Answer 20

explicitly converting a value from one type to a different type. For example, the cast from a floating-point number x to an integer is expressed in Java by the cast notation (int) x.

Question 21

Church-Turing Thesis

Answer 21

in computability theory, the Church–Turing thesis (also known as the Turing–Church thesis,[1] the Church–Turing conjecture, Church’s thesis, Church’s conjecture, and Turing’s thesis) is a combined hypothesis (“thesis”) about the nature of functions whose values are effectively calculable; or, in more modern terms, functions whose values are algorithmically computable. In simple terms, the Church–Turing thesis states that a function is algorithmically computable if and only if it is computable by a Turing machine

Question 22

class

Answer 22

a programmer-defined data type

Question 23

compiler

Answer 23

a program that translates code in a high-level language (such as Java) to machine instructions (such as bytecode for the Java virtual machine)

Question 24

computability

Answer 24

computability is the ability to solve a problem in an effective manner. It is a key topic of the field of computability theory within mathematical logic and the theory of computation within computer science. The computability of a problem is closely linked to the existence of an algorithm to solve the problem.

Question 25

computer network

Answer 25

a computer network or data network is a telecommunications network that allows computers to exchange data. In computer networks, networked computing devices pass data to each other along data connections. The connections (network links) between nodes are established using either cable media or wireless media. The best-known computer network is the Internet

Question 26

computer science

Answer 26

the study of algorithms including their formal and mathematical properties, their hardware realizations, their linguistic realizations, and their applications

Question 27

computing agent

Answer 27

any object capable of understanding and executing our instructions.

Question 28

constructor

Answer 28

a sequence of statements for initializing a newly instantiated object

Question 29

control unit

Answer 29

unit within the computer that actually carries out the operations of a program

Question 30

DASD

Answer 30

in mainframe computers and some minicomputers, a direct access storage device, or DASD, is any secondary storage device which has relatively low access time relative to its capacity

Question 31

DNS

Answer 31

the Domain Name System (DNS) is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network

Question 32

ethernet

Answer 32

Ethernet is a family of broadband computer networking technologies for local area networks (LANs). Ethernet was commercially introduced in 1980 and standardized in 1985 as IEEE 802.3. Ethernet has largely replaced competing wired LAN technologies such as token ring, FDDI, and ARCNET

Question 33

encapsulation

Answer 33

the hiding of implementation details

Question 34

explicit parameter

Answer 34

a parameter of a method other than the object on which the method is invoked

Question 35

flops

Answer 35

floating-point operations per second

Question 36

formal parameter

Answer 36

a variable in a method definition

Question 37

gigabyte

Answer 37

2^30, or close to a billion, bytes

Question 38

Halting Problem

Answer 38

in computability theory, the halting problem can be stated as follows: "Given a description of an arbitrary computer program, decide whether the program finishes running or continues to run forever". This is equivalent to the problem of deciding, given a program and an input, whether the program will eventually halt when run with that input, or will run forever.

Question 39

HTTP

Answer 39

(Hypertext Transfer Protocol) the protocol that defines communication between web browsers and web servers

Question 40

I/O buffer

Answer 40

memory stored in the I/O controller for transfer between RAM and an I/O device

Question 41

I/O controller

Answer 41

a device that interfaces between an input or output device and the computer or hardware device. The input/output controller on a computer is commonly located on the motherboard. However, an I/O controller can also be an internal add-on that can either be used as a replacement or to allow for additional input or output devices for the computer.

Question 42

IDE

Answer 42

(Integrated Development Environment) a programming environment that includes an editor, compiler, and debugger

Question 43

implicit parameter

Answer 43

the object on which a method is invoked. For example, in the call x.f(y), the object x is the implicit parameter of the method f.

Question 44

interface (in Java)

Answer 44

an interface in the Java programming language is an abstract type that is used to specify an interface (in the generic sense of the term) that classes must be implement. Interfaces are declared using the interface keyword, and may only contain method signature and constant declarations (variable declarations that are declared to be both static and final). An interface never contains method implementations (ie function "bodies").

Question 45

inheritance (in Java)

Answer 45

The is-a relationship between a more general superclass and a more specialized subclass.

Question 46

initialize

Answer 46

set a variable to a well-defined value when it is created

Question 47

instance

Answer 47

(of a class) an object whose type is that class

Question 48

instance variable

Answer 48

a variable defined in a class for which every object of the class has its own value

Question 49

instantiation

Answer 49

(of a class) construction of an object of that class

Question 50

Internet Protocol

Answer 50

The network layer of the internet. Delivers packages from the source host to a destination based on IP addresses, and defines addressing methods.

Question 51

instruction register

Answer 51

Holds a copy of the instruction fetched from memory, which includes the op code and addresses. Instruction decoders interpret op codes to find the corresponding functions, and the address tells the computer where to do this function.

Question 52

instruction set

Answer 52

an instruction set, or instruction set architecture (ISA), is the part of the computer architecture related to programming, including the native data types, instructions, registers, addressing modes, memory architecture, interrupt and exception handling, and external I/O.

Question 53

kilobyte

Answer 53

2^10, or around 1000, bytes

Question 54

LAN

Answer 54

Local Area Network. Connects hardware devices such as computers, printers, and storage devices. There are many types: bus, ring, star, etc.

Question 55

local variable

Answer 55

a variable whose scope is a block (it can only be accessed within that block)

Question 56

logic gate

Answer 56

an idealized or physical device implementing a Boolean function, that is, it performs a logical operation on one or more logic inputs and produces a single logic output

Question 57

loop

Answer 57

a sequence of instructions that is executed repeatedly

Question 58

MAC

Answer 58

Medium Access Control. Determine how to arbitrate ownership of a shared communication line when multiple nodes want to send messages at the same time. Node listens to see if the line is busy before it sends. If two messages are sent at the same time they collide and are lost. Retransmission selects a random waiting time to resend the messages.

Question 59

machine language

Answer 59

(machine code) instructions that can be executed directly by the CPU

Question 60

mass storage

Answer 60

nonvolatile means of storing information, can store a great deal of memory, don’t require a power source in order to persist, two distinct forms - direct access storage devices (DASDs) and sequential access storage devices (SASDs)

Question 61

megabyte

Answer 61

2^20, or around a million, bytes

Question 62

memory

Answer 62

fundamental unit of a computer that stores and retrieves the instructions and the data being executed

Question 63

Memory Address Register (MAR)

Answer 63

holds the address of the cell to be fetched or stored

Question 64

Memory Data Register (MDR)

Answer 64

contains the data value being fetched or stored

Question 65

method

Answer 65

sequence of statements that has a name, may have formal parameters, and may return a value, a method can be invoked any number of times, with different values for its parameters

Question 66

mutator method

Answer 66

a method that changes the state of an object

Question 67

object

Answer 67

a value of a class type

Question 68

object reference

Answer 68

a value that denotes the location of an object in memory. In Java, a variable whose type is a class contains a reference to an object of that class

Question 69

object-oriented programming

Answer 69

designing a program by discovering objects, their properties, and their relationships

Question 70

op code

Answer 70

3-bits, has 8 possible output line. They are fed into an instruction decoder to find the corresponding operation that goes with the 3 bits.

Question 71

operating system

Answer 71

the software that launches application programs and provides services (such as a file system) for those programs

Question 72

overloading a method

Answer 72

giving more than one meaning to a method name

Question 73

overriding a method

Answer 73

redefining a method in a subclass

Question 74

parameter

Answer 74

an item of information that is specified to a method when the method is called

Question 75

parameter passing

Answer 75

specifying expressions to be arguments for a method when it is called

Question 76

portability

Answer 76

a program that will run, without change, on multiple platforms. The java compiler is ale to achieve this because it does not translate Java programs into CPU instructions, but compiles for the Java virtual machine, a program that simulates a real CPU.

Question 77

primitive data type

Answer 77

in Java, a number type or boolean

Question 78

protocol

Answer 78

in networking, a protocol is a mutually agreed-upon set of rules, conventions, and agreements for the efficient and orderly exchange of information

Question 79

protocol stack

Answer 79

five layers (from top to bottom): application, transport, network, logical link control, medium access control, and physical. This hierarchy is called the TCP/IP protocol.

Question 80

pseudocode

Answer 80

a high-level description of the actions of a program or algorithm, using a mixture of English and informal programming language syntax

Question 81

Random Access Memory

Answer 81

RAM, electronic circuits in a computer that can store code and data of running programs

Question 82

register

Answer 82

a storage cell that holds the operands of an arithmetic operation and that, when the operation is complete, holds its results

Question 83

SASD

Answer 83

Sequential Access Storage Devices. Does not require that all units of data be identifiable by unique addresses; searches all data sequentially. It is very, very slow.

Question 84

scope

Answer 84

the part of a program in which a variable is defined

Question 85

software

Answer 85

the intangible instructions and data that are necessary for operating a computer or another device

Question 86

static variable

Answer 86

a variable defined in a class that has only one value for the whole class, and which can be accessed and changed by any method of that class

Question 87

static method

Answer 87

a method with no implicit parameter

Question 88

stored program concept

Answer 88

central characteristic of Von Neumann Architecture and the design of all modern computers, in which the instructions to be executed by the computer are represented as binary values and stored in memory

Question 89

syntax

Answer 89

rules that define how to form instructions in a particular programming language

Question 90

terabyte

Answer 90

2^40, or around 1 trillion, bytes

Question 91

time complexity

Answer 91

the amount of time taken by an algorithm to run as a function of the length of the string representing the input. Often denoted by the big O notation: O(n).

Question 92

transistor

Answer 92

the elementary building block of all modern computers, a solid-state device with no moving parts that can be in either an on or off state, transistors as well as electrical conducting paths to them are printed photographically on a wafer of silicon to produce an integrated circuit or chip

Question 93

TCP

Answer 93

Transport Control Protocol. Also called protocol stack, has five layers (from top to bottom): application, transport, network, logical link control, medium access control, and physical.

Question 94

truth table

Answer 94

a mathematical table used to compute the functional values of logical expressions on each possible combination of their logical variables

Question 95

Turing machine

Answer 95

a very simple model of computation that is used in theoretical computer science to explore computability of problems

Question 96

Von Neumann architecture

Answer 96

theoretical model for nearly all modern computers, such computers are composed of four major subsystems (memory, input/output, the ALU or arithmetic/logic unit, and the control unit), the stored program concept, and the sequential execution of instructions

Question 97

white space

Answer 97

any sequence of only space, tab, and newline characters

Question 98

WAN

Answer 98

Wide Area Networks. Connects devices that are not in close proximity (across the country, for example). They use dedicated, point to point links and a store and forward, packet-switched tech to send messages.