# Computer science glossary 1 up to 389(priorities)

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- Created by: George Heard
- Created on: 29-03-19 09:37

Vectored interrupt mechanism

A method of handling interrupts be pointing to the first memory address of the instructions needed

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Two's complement

A method of working with signed binary values

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Unsigned binary

Binary that represents positive numbers only

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Vector graphics

A graphic consisting of components defined by geometric formulae and associated properties, such as line colour and style

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Picture element (pixel)

The smallest identifiable component of a bitmap image, defined by just two properties: its position in the bitmap matrix and its colour

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Kibi

A prefix representing the fact 2X10 (1024) written as the symbol Ki

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Mebi

a prefix representing the fact 2X20 (1048576) written as the symbol Mi

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Gibi

A prefix representing the fact 2X30 written as the symbol Gi

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Lossless compression

Coding techniques that allow subsequent decoding to recreate exactly the original file

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Lossy compression

Coding techniques that cause some information to be lost so that the exact original file cannot be recovered in subsequent decoding

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Router

A device that acts as a node on the internet

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Gateway

A device that connects networks of different underlying technologies

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Server

A device that provides services via a network

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IPv4 address

A 32-bit long, hierarchical address of a device on the internet

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Domain name system (DNS)

A hierarchical distributed database installed on domain name servers that is responsible for mapping a domain name to an IP address

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Random-access memory (RAM)

Volatile memory that can be read from or written to any number of times

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Read-Only memory (ROM)

Non-volatile memory that cannot be written to but can be read from any number of times

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Memory address

A specific location in memory where instructions or date are stored

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Assignment

The process of giving a value to a variable or constant

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Constant

An item of data whose value does not change

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Variable

An item of data whose value could change while the program is being run

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Debug

The process of finding and correcting errors in programs

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Declaration

The process of defining variable and constants in terms of their name and data type

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Data type

Determines what sort of data are being stored and how it will be handled by the program

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Integer

Any whole positive or negative number including zero

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pointer

A data item that identifies a particular element in a data structure - normally the front or rear

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Array

A set of related data items stored under a single identifier. Can work on one or more dimensions

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Element

A single value within a set or list - also called a member

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Record

One line of a text file

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Syntax

The rules of how words are used within a given language

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Selection

The principles of choosing what action to take based on certain criteria

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Nesting

Placing one set of instructions within another set of instructions

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Iteration

The principles of repeating processes

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Definite Iteration

A process that repeats a set number of times

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Indefinite iteration

A process that repeats until a certain condition is met

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Loop

A repeated process

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Sequence

The principle of putting the correct instructions in the right order within a program

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Arithmetic operation

Common expressions such as +,-,/,*

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Rounding

Reducing the number of digits used to represent a number while maintaining a value that is approximately equivalent

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Truncating

The process of cutting off a number after a certain number of characters or decimal places

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Random number generation

A function that produces a completely random number

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Pseudo-Random number generator

Common in programming languages, a function that produces a random number that is not 100% random

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Relational operations

Expressions that compare two values such as equal to or greater than

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Boolean operations

Expressions that result in a TRUE or FALSE value

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AND + pic

Boolean operation that outputs true if both inputs are true

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OR + pic

Boolean operations that outputs true if either of its inputs are true

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NOT + pic

Boolean operations that inverts the result so true becomes false and false becomes true

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XOR + pic

Boolean operation that is true if either input is true but not if both inputs are true

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String handling functions

Actions that can be carried out on sequences of characters

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Character code

A binary representation of a particular letter, number or special character

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Subroutine

A named block of code designed to carry out a specific task

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Procedure

Another term for a subroutine

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Subprogram

Another term for a subroutine

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Routine

Another term for a subroutine

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Local variable

A variable that is available only in specified subroutines and functions

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Global variable

A variable that is a available anywhere in the program

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Function

A subroutine that returns a value

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Functional programming

A programming paradigm that uses functions to create programs

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Parameter

Data being passed into a subroutine

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Argument

An item of data being passed to a subroutine

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Block interface

Code that describes the data being passed from one subroutine to another

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Exception handling

The process of dealing with events that cause the current subroutine to stop

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Procedural programming languages

Languages where the programmer specifies the steps that must be carried out in order to achieve a result

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Imperative programming languages

Languages based on giving the computer commands or procedures to follow

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Hierarchy chart

A diagram that shows the design of a system from the top down

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Structure chart

Similar to a hierarchy chart with the addition of showing how data are passed around the system

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Top-Down approach

When designing systems it means that you start at the top of the process and work your way down into smaller and smaller sub-processes

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flowchart

a digram using standard symbols that describes a process or system

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System flowchart

A diagram using standard symbols that desribes a process or system

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Pseudo-code

A method of writing code that does not require knowledge of a particular programming language

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Naming conventions

The process of giving meaningful names to subroutines, functions, variables and other user-defined features in a program

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Dry run

The process of stepping through each line of code to see what will happen before the program is run

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Trace table

A method of recording the result of each step that takes place when dry running code

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Modular design

A method of system design that breaks a whole system down into smaller units, or modules

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Exncapsulation

The concept of putting properties, methods and data in one object

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method

The code or routings contained within a class

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Properties

The defining features of an object or class in terms of its data

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Class

defines the properties and methods of a group of similar objects

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Object

A specific instance of a class

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Inheritance

The concept that properties and methods in one class can be shared with a subclass

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class diagrams

A way of representing the relationship between classes

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Instantiation

The process of creating an object from a class

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Polymorphism

The ability of different types of data to be manipulated with the same method

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Overriding

Where a method described in the subclass takes precedence over a method with the same name in the base class

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Composition aggregation

Creating an object that contains other objects, and will cease to exist if the containing object is destroyed

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Association aggregation

Creating an object, that contains other objects, which can continue to exist even if the containing object is destroyed

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data structure

A common format for storing large volumes of related data, which is an implementation of an abstract data type

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Abstract data type

A conceptual model of how data can be stored and the operations that can be carried out on the data

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File

A collection of related data

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Array

A set of related data items stored under a string identifier. Can work on one or more dimensions

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Text file

A file that contains human- readable characters

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Binary file

Stores data as sequences of 0s and 1s

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Record

One line of a text file

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Field

An item of data

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Queue

A data structure where the first item added is the first removed

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Stack

A data structure where the last item added is the first item removed

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Static data structure

A method of storing data where the amount of data stored (and memory used to store it) will vary as the program is being run

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dynamic data structure

A method of storing data where the amount of data stored(and memory used to store it) will vary as the program is being run

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Heap

A pool of unused memory that can be allocated to a dynamic data structure

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Stack frame

A collection of data about a subroutine cell

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Call stack

A special type of stack used to store information about active subroutines and functions within a program

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Interrupt

A signal sent to a device or program to the processor requesting its attention

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Nesting

The process of putting one statement inside another statement

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Recursion

The process of a subroutinge calling itself

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Queue

A FIFO structure where data leaves in the order it arrives

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FIFO

first in first out refers to a data structure such as a queue where the first item of data entered is the fist item of data to leave

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Linear queue

A FIFO strucutre implemented as a ring where the front and read pointers can wrap aroudn from the end to the start of the array

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Priority queue

A variation of a FIFO structure where some data may leave out of sequence where it has a higher priority than other data items

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Circular queue

A FIFO data structrure implemented as a ring where the front and read pointers can wrap around from the end to the start of the array

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Graph theory

The underlying mathematical principles behind the use of graphs

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Arc

A join or relationship between two nodes - also known as an edge

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Vertex/vertices

An object in a graph - also known as a node

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Weighted graph

A graph that has a data value labelled on each edge

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Undirected graph

A graph where the relationship between vertices is two-way

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Directed graph

A graph where the relationship between vertices is one-way

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Latency

The time delay that occurs when transmitting data between devices

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Adjacency list

A data structure that stores a list of nodes with their adjacent nodes

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Tree

A data structure similar to a graph, with no loops

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Node

An object in a graph-also known as a vertex

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Edge

A join of relationship between nodes also known as an arc

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Root

The starting node in a rooted tree structure from which all other nodes branch off

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Parent

A type of node in a tree, where there are further nodes below it

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Child

A node in a tree that has nodes above it in the hierarchy

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Leaf

A node that does not have any other nodes beneath it

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Binary tree

A tree where each node can only have up to two child nodes attatched to it

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Hash table

A data structure that stores key/value pairs based on an index calculated from an algorithim

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Key/value pair

The key and its associated data

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Hashing algorithim

Code that created a unique index from given items of key data

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Cache

A high- speed temporary area of memory

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Collision

When a hasing algorithim produces the same index for two or more different keys

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Clustering

When a hashing algorithim produces indices that are not randomly distributed

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Load factor

The ratio of how many indices are available to how many there are in total

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index

The location where values will be stored, calculated from the key

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Chaining

A technique for generating a unique index when there is a collision by adding the key/value to a list stored at the same index

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Rehashing

The process of running the hashing algorithm again when a collision occurs

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Dictionary (data structure)

A data structure that maps key data

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Associative array

A two-dimensional structure containing key/value pairs of data

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Magnitude

One of the two components of a vectore - refers to its size

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Direction

One of the two components of a vector

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Components

Teh values within a vector

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Scalar

A real value used to multiplu a vector to scale the vectore

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Dot product

Multiplying two vectors toether to produce a number

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Convex combination

A method of multiplying vectors that produces a resulting vector within the convex hull

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Vector space

A collection of elements that can be formed by adding or multiplying vectors together

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Convex hull

A spatial representation of the vector space between two vectors

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Implementation

Creating code to produce a programmed solution

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Array

A set of data items of the same type grouped together with the same identifier

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Edge

A connection between two nodes in a graph or tree structure

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Graph

A data type made up of nodes and edges

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Breadth first

A method for traversing a graph that explores nodes closest to the starting node first before progressively exploring nodes that are further away

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Depth first

A method for traversing a graph that starts at a chosen node and explores as far as possible along each branch away from the starting node before backtracking

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Queue

A data structure where the first item added is the first item removed

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Node

Elements of a graph or tree

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Binary tree

A structure where each node can only have up to two nodes attached to it

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Pre-order

A method of traversing a tree by visiting the root, traversing the left subtree and traversing the right subtree

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In-order

A method of traversing a tree by traversing the left subtree, visiting the root and traversing the right subtree

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Post-order

A method of traversing a tree by traversing the left subtree, traversing the right subtree and then visiting the root

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Traversal

The process of reading data from a tree or graph by visiting all of the nodes

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Binary search

A technique for searching data that works by splitting datasets in held repeatedly until the search data is found

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Recursion

A technique where a function can call itself in order to complete a task

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Single source

In Dijkstra's algorithm it means that the shortest path is calculated

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Shortest path

The shortest distance between two vertices based on the weighting of the edges

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Linear search

A simple search technique that looks through data one item at a time until the search term is found

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Binary search

A technique for searching data that works by splitting datasets in half repeatedly until the search data is found

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Binary tree search

A technique for searching a binary tree that traverses the tree until the search term is found

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Reverse polish Notation (RPN)

Another term for postfix notation (a mathematical notation in which operators follow their operands)

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Infix

Expressions that are written with the operators within the operands e.g. 2+3

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Operator

The mathematical process within an expression

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SODMAS

A methodology for evaluation mathematical expressions in a particular sequence

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Polish notation

Another way of describing prefix notation(where operators precede their operands

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Interpreter

Software that translates and executes programs line by line by converting programming statements either into machine code or by calling instructions to carry out the high-level language statements

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Operand

A value within an expression

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Prefix

Expressions that are written with the operators before the operands e.g. + 2 3

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Postfix

Expressions that are written with the operators after the operands e.g. 2 3 +

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In-order traversal

A method of extracting data from a binary tree that will result in an infix expression

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Post-order traversal

A method of extracting data from a binary tree that will result in postifx expressions

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Pre-order traversal

A method of extracting data from a binary tree that will result in prefix expressions

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Vector graphics

An image made up of objects and coordinates

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Bubble sort

A technique for putting data in order by repeatedly stepping through an array, comparing adjacent elements and swapping them if necessary until the array is in order

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Iteration

repeating the same process several times in order to achieve a result

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Merge sort

A technique for putting data in order by splitting lists into single elements and then merging them back together again

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Logical reasoning

The process of using a given set of facts to determine whether new facts are true or false

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Algorithm

A sequence of instructions

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Representational abstractions

The process of removing unnecessary details so that only information that is required to solve the problem that remains

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Abstraction by generalisation categorisation

The concept of reducing problems by putting similar aspects of a problem into hierarchical categories

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Top-down design

related to the modular approach, this starts with the main system at the top and breaks it down into smaller and smaller units a bit like a family tree

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Functional abstraction

Breaking down a complex problem into a series of reusable functions

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Data abstractions

Hiding how data is represented so that it is easier to build a new kind of data object e.g. building a stack from an array

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Problem abstraction

removing unnecessary details in a program until the underlying problem is identified to see if this is the same as a problem that has been already solved

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Information hiding

The process of hiding all details of an object that do not contribute to its essentials characteristics

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Decomposition

Breaking down a large task into a series of subtasks

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Composition aggregations

Building up a while system from smaller units. The opposite of decomposition

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Finite

Countable

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Finite state machine (FSM)

any device that stores its current status and whose status can change as the result of an input. Mainly used a conceptual model for designing and describing systems

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State transition diagram

A visual representation of an FSM using circles and arrows

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Accepting state

The state that identifies whether an input has been accepted

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State Transition table

A tabular representation of an FSM showing inputs, current state and the next state

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Mealy machine

A type of finite state machine with outputsq

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Cipher

An algorithm that encrypts and decrypts data, also known as code

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Shift Cipher

A simple substation cipher where the letters are coded by moving a certain amount forward or backwards in the alphabetq

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Turing machine

A theoretical model of computation

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Read/write head

The theoretical device that writes or reads from the current call of a tape in a turing machine

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Halting state

Stops the turing machine

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Start state

The initial state of a turing machine

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Transition function / rule

A method of notating how a turing machine moves from one state to another and how the data on the tape changes

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State transition diagram

A visual representation of the transition function of a turing machine

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Instruction table

A method of describing a turing machine in tabular form

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Universal machine

A machine that can simulate a turing machine by reading a description of the machine along with the input of its own tape

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Regular language

Any language that can be described using regular expressions

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Regular expression

Notation that contains strings of characters that can be matched to the contents of a set

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Context - feee language

An unambiguous way of describing the syntax of a language useful where the language is complex

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Backus-Naur Form (BNF)

A form of notation for describing the syntax used by a programming language

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Set

A collection of symbols in any order that do not repeat

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Terminal

In BNF, it is the final element that requires no further rules

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Syntax diagram

A method of visualising rules written in BNF or any other context - free language

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Natural number

A positive whole number including zero

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Set building

The process of creating sets by describing them using notation rather than listing the elements

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Member

Describes a value or element that belongs to a set

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Empty set

The set that contains no values

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Finite set

A set where the elements can be counted using natural number up to a particular number

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Infinite set

A set that is not finite

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Cardinality

The umber of elements in a set

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Countable set

A finite set where the elements can be counted using natural numbers

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Countably infinite sets

Where the elements can be put into a one-to-two correspondence with the set of natural numbers sets

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Cartesian product

Combining the elements of two or more sets to create a set of ordered pairs

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Union

Where two sets are joined and all of the elements of both sets are included in the joined set

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Intersection

Describes which elements are common to both sets when two sets are joined

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Difference

Describes which elements differ when two sets are joined together

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Subset

A set where the elements of one are entirely contained within the other; can include two sets that are exactly the same

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Proper subset

Where one set is wholly contained within another and the other set has addition elements

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Function

relates each element of a set with the element of another set

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Domain

All the values that may be input to a mathematical function

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Codomain

All the values that may be input to a mathematical function

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Factorial

The product of all positive integers less than or equal to n e.g. 3! is 3*2*1

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Space complexity

The concept of how much space an algorithm requires

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input size

In big o notation the size of whatever you asking to work with e.g. data, parameters

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Time complexity

The concept of how much time an algorithm requires

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constant time

In big 0 notation where the time taken to run an algorithm does not vary the input size

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Linear time

In big 0 notation where the time taken to run and algorithm increases in direct proportion with the input size

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Exponential time

In big 0 notation where the time taken to run an algorithm increases as an exponential function of the number of inputs. E.g. for each additional input the time taken might double

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Logarithmic time

In big 0 notation where the time taken to run and algorithm increased or decreased in line with a logarithm

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Polynomial time

In big 0 notation where the time taken to run the algorithm is a polynomial function of the input size

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Tractable problem

A problem that can be solved in an acceptable amount of time

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Intractable problem

A problem that cannot be solved within an acceptable time frame

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Heuristic

With algorithms it is a method for producing a 'rule of thumb' to produce an acceptable solution to intractable problems

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Unsolvable problem

A problem that it has been proved cannot be solved on a computer

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Halting problem

An example of an unsolvable problem where it is impossible to write aprogram that can work out whether another problem will halt given a particular input

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Natural number

A positive whole number including zero

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rational number

Any number that can be expressed as a fraction or ratio of integers

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Irrational number

A number that cannot be represented as a fraction or ratio as the deciaml form will contain infinite repeating values

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Real number

Any positive or negative number with or without a fractional part

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Ordinal number

A number used to identify position relative to other numbers

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Cardinal numbers

A number that identifies the size of something

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Well-ordered set

A group of related numbers with a defined order

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Array

A data structure where data items are grouped together under a single identifier and are then accessed based on their position

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Number base

The number of digits available within a particular number system e.g. base 10 for a decimal base 2 for binary

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Bit

A single binary digit from a binary number- either a zero or a one

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Unit

The grouping together of bits or bytes to form larger . blocks of measurement e.g. MB, GB

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Unsigned binary

Binary that represents positive number only

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Fixed point

Where the decimal/binary point is fixed within a number

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Floating point

Where the decimal/binary point can move within a number

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signed binary

Binary with a positive or negative sign

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overflow

When a number is too large to be represented with the number of bits allocated

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Underflow

When a number is too small to be represented with the number of bits allocated

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Normalisation

A process for adjusting numbers onto a common scale

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Precision

How accurate a number is

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Mantissa

The significant digits that make up a number

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Exponential time

The "power of" part of a number indicating how far a binary point should be shifted left or right

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Character code

A binary representation of a particular letter, number or special character

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ASCII

A standard binary coding system for characters and numbers

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Unicode

A standard binary coding system that has superseded ASC!!

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Parity bit

A method of checking binary codes by counting the number of 0s and 1s in the code

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Majority voting

A method of checking for errors by producing the same data several times and checking it is the same each time

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Check digit

A digit added to the end of binary data to check the data is accurate

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Bit-mapped graphic

An image made up of individual pixels

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Pixel

An individual picture element

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Resolution

Width x height or pixels per inch

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Colour depth

The number of bits or bytes allocated to represent the colour of a pixel in a bit-mapped graphic

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Vector graphic

An image made up of objects and coordinates

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Compresssion

The process of reducing the number of bits required to represent data

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Run-length coding

A method of compressing by eliminating repeated data

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Dictionary-based encoding

a method of compressing text files

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Encryption

the process of turning plaintext into scrambled ciphertext, which can only be understood if it is decrypted

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Decryption

The process of deciphering encrypted data or mesages

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Plaintext

Data in human-readable form

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Cipher text

encrypted data

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Caesar cipher

A substitution cipher where one character of plaintext is substituted for another which becomes the ciphertext

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Vernam cipher

A method of encryption that uses a one-time pad(key) to create cipher text that is mathematically impossible to decrypt without the key

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Transposition cipher

A method of encryption where the characters are rearranged to form an anagram

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Key

In cryptography it is the data that is used to encrypt and decrypt the data

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Substitution cipher

A method of encryption where one character is substituted for another to create cipher text

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Polyalphabetic

Using more than one alphabet

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Frequency analysis

In cryptography it is the study of how often different letters or phrases are used

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Railfence cipher

A type of transposition cipher that encodes the message by splitting it over rows

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Route cipher

A type of transposition cipher that encodes the message by placing it into a grid

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One-time pad

A key that is only used once to encrypt and decrypt a message and is then discarded

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Baudot code

A five-digit character code that predates ASCII and unicode

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Computational security

A concept of how secure data encryption is

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Computational hardness

The degree of difficulty in cracking a cipher

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Hardware

A generic term for the physical parts of the computer ,both internal and external

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Software

A generic term for any program that can be run on a program

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Application software

Programs that perform specific tasks that would need doing even if computers didn't exist e.g. editing text, carrying our calculations

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Utility programs

Programs that perform specific common task related to running the computer e.g. zipping files

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Library programs

Code, data and resources that can be called by other programs

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Translators

Software that converts programming language instructions into 0s and 1s (machine code) There are three types - compilers, assemblers

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Compiler

A program that translates a high-level language into machine code by translating all of the code

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Assembler

A program that translates a program written in assembly language into machine code

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Interpreter

A program for translating a high-level language by reading each statement in the source code and immediately performing the action

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Operating system software

A suite of programs designed to control the operations of the computer

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Virtual machine

The concept that all of the complexities of using a computer are hidden from the user and other software by the operating system

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Resource management

How an operating system manages hardware and software to optimise the performance of the computer

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Processor

A device that carries out computation on data by following instructions, in order to produce an output

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Scheduling

A technique to ensure that different users or different programs are able to work on the same computer system at the same time

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Memory management

How the operating system uses RAM to optimise the performance of the omputer

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File management

How an operating system stores and retrieves files

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Machine code

The lowest level of code mad up of 0s and 1s

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Assembly language

A way of programming that involves writing mnemonics

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Mnemonics

Short codes that are used as instructions when programming e.g. LDR , ADD

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Source code

Programming code that has not been compiled into an executable file

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Assembler

A program that translates a program written in assembly language into machine code

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Object code

Compiled code that can be run as an executable on any computer

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Low-level language

Machine code and assembly language

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High-level language

A programming language that allows programs to be written using english key words and that is platform independant

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Imperative language

A language based on giving the computer command or procedures to follow

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Object-oriented language

A programming paradigm that encapsulates instructions and data together into objects

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Declarative languages

Languages that declare of specify what properties a result should have e.g. results will be based on functions

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Functional language

A programming paradigm that uses mathematical functions

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Translator

The general name for any program that translates code from one language to another e.e.g translating source code into machine code

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Interpreter

A program for translating a high-level language by reading each statement in the source code and immediately performing the action

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Compiler

A program that translates a high-level language into machine code by translating all of the code

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Bytecode

An instruction set used for programming that can be executed on any computer using a virtual machine

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Truth table

A method of representing/ calculating the result of every possible combination or inputs in a boolean expression

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AND gate

result is true if both inputs are true

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OR

Boolean operation that outputs true if either of its inputs are true

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NOT

Boolean operation that inverts the result so true becomes false and false becomes true

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NAND

Boolean operation that outputs true if any of the inputs are false

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NAND gate

Result is true if any of the inputs are false

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NOR

Boolean operation that outputs true if all of its inputs are false

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NOR gate

Result is true if both inputs are false

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XOR

Boolean operation that is true if either input is true but not if both inputs are true

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De Morgan's law

A process for simplifying boolean expressions

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Logic gate

An electronic component used to perform boolean algorithms

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Boolean expressions

An equation made up of boolean operations

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AND gate

Result is true if both inputs are true

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OR gate

Result is true if either input is true

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Not gate

Inverts the result so true becomes false and false becomes true

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NAND gate

Result is true if any of the inputs are false

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XOR gate

Result is true if either input is true but not if both inputs are true

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NOR gate

Result is true if both inputs are false

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Logic circuit

A combination of logic gates

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Arithmetic logic unit (ALU)

Part of the processor that processes and manipulates data

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Half adder

A circuit that performs addition using inputs from A and B only

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Full adder

A circuit that performs addition using inputs from A and B plus a carry bit

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Carry bit

Used to store a 0 or 1 depending on the result of binary addition

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Flip-Flop

A memory unit that can store one bit

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Edge-triggered D-type Flip-flop

A memory unit that changes state with each pulse of the clock

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Clock

A device that generates a signal used to synchronise the components of a computer

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Processor

A device that carries out computation on data by following instructions, in order to produce an output

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Main memory

stores data and instructions that will be used by the processor

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Fetch-execute cycle

The continuous process carried out by the processor when running programs

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Chip

An electronic component contained within a thin slice of silicon

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Bus

Microscopic parallel wires that transmit data between internal components

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Data bus

Transfers data between the processor and memory

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Input/Output (I/O) controller

Controls the flow of information between the process and the input and output devices

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word length

The number of bits that can be addressed, transferred or manipulated as one unit

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Address bus

Used to specify a physical address in memory so that the data bus can access it

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Addressable memory

The concept that data and instructions are stored in memory using discrete addresses

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Control bus

Controls the flow of data between the processor and other parts of the computer

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Von neumann architecture

A technique for building a processor where data and instructions are stored in the same memory and accessed via buses

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Harvard architecture

A technique for building a processor that uses separate buses and memory for data and instructions

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Stored program concept

The idea that instructions and data stored together in memory

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Fetch-execute cycle

The continuous process carried out by the processor when running programs

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Control unit

Part of the processor that manages the execution of instructions

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Arithmetic logic unit (ALU)

part of the processor that processes and manipulates data

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Clock

A device that generates a signal used to synchronise components of a computer

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Register

A small section of temporary storage that is part of the processor. Stores data or control instruction during the fetch-decode-execute cycle

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Status register

Keeps track of the various functions of the computer such as if the result of the last calculation was positive or negative

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Interrupt register

Stores details of incoming interrupts

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Current instruction register(SIR)

register that stores the instructions that the CPU is currently decoding/executing

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Program counter(PC)

Register that stores the address of the next instruction

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Stored program concept

The idea that instructions and data are stored together in menory

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Status register

keeps track of the various functions of the computer such as if the result of the last calculation was positive or negative

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Memory Buffer register (MBR)

register that holds data that is either written to or copied from the CPU

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Memory data register (MDR)

another name for the MBR

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Bus width

The number of bits that can e sent down a bus in one go

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Word length

The number of bits that can be addressed, transferred or manipulated as one unit

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Multi-core

A chip with more than one processor

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interrupt service routine

Calls the routine required to handle an interrupt

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Priorities

A method for assigning importance to interrupts in order to process them in the right order

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## Other cards in this set

### Card 2

#### Front

Two's complement

#### Back

A method of working with signed binary values

### Card 3

#### Front

Unsigned binary

#### Back

### Card 4

#### Front

Vector graphics

#### Back

### Card 5

#### Front

Picture element (pixel)

#### Back

## Similar Computing resources:

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