Chapter 1 Definitions

Question 1

Define bit

Answer 1

The basic computing element that is either 0 or 1, and is formed from the words Binary digit

Question 2

Define binary number system

Answer 2

A number system based on 2 and can only use the values 0 and 1

Question 3

Define hexadecimal number system

Answer 3

A number system based on the value 16 which uses denary digits 0 to 9 and letters A to F

Question 4

Define error code

Answer 4

An error message generated from the computer

Question 5

Define MAC address

Answer 5

Standing for Media Access Control, this address (given in hexadecimal) uniquely identifies a device on the internet

Question 6

Define IP address

Answer 6

Internet Protocol; identified either as IPv4 or IPv6; it gives a unique address to each device connected to a network identifying their location

Question 7

Define HTML

Answer 7

HyperText Mark-up Language is used in the design of web pages and to write

Question 8

Define overflow error

Answer 8

The result of carrying out a calculation that produces a value that is too large for the computer’s allocated word size

Question 9

Define logical shift

Answer 9

An operation that shifts bits to the left or right in a register; any bits shifted out of a register are replaced with zeroes

Question 10

Define two’s complement

Answer 10

A method of representing negative numbers in binary; when applied to an 8-bit system, the left-most bit is given the value -128

Question 11

Define ASCII code

Answer 11

A character set for all the characters on a standard keyboard and control codes

Question 12

Define character set

Answer 12

A list of the characters that have been defined by computer hardware and software. The character set is necessary so that the computer can understand human characters.

Question 13

Define Unicode

Answer 13

A character set which represents all the languages of the world

Question 14

Define sampling resolution

Answer 14

The number of bits used to represent sound amplitude in digital sound recording (also known as bit depth)

Question 15

Define bit depth

Answer 15

The number of bits used to represent the smallest unit of a sound file

Question 16

Define colour depth

Answer 16

The number of bits used to represent the colours of a pixel

Question 17

Define sampling rate

Answer 17

The number of sound samples taken per second in digital sound recording

Question 18

Define bitmap image

Answer 18

An image made up of pixels

Question 19

Define pixel

Answer 19

Derived from the term ‘picture element’. This is the smallest element used to make up an image on a display

Question 20

Define image resolution

Answer 20

The number of pixels in the X-Y direction of an image

Question 21

Define pixelated (image)

Answer 21

This is the result of zooming into a bitmap image; on zooming out, the pixel density can be diminished to such a degree that the actual pixels themselves can be seen

Question 22

Define pixel density

Answer 22

Number of pixels per square inch

Question 23

Define compression

Answer 23

Reduction of the size of a file by removing repeated or redundant pieces of data; this can be lossy or lossless

Question 24

Define bandwidth

Answer 24

The maximum rate of transfer of data across a network, measured in kilobits per second (kbps) or megabits per second (Mbps)

Question 25

Define lossy file compression

Answer 25

A file compression method in which parts of the original file cannot be recovered during the decompression process

Question 26

Define lossless file compression

Answer 26

A file compression method that allows the original file to be fully restored during the decompression process

Question 27

Define audio compression

Answer 27

A method used to reduce the size of a sound file using perceptual music shaping

Question 28

Define MP3

Answer 28

A lossy file compression method used for music files

Question 29

Define MP4

Answer 29

A lossy file compression method used for multimedia files

Question 30

Define JPEG

Answer 30

From the Joint Photographic Expert Group; a form of lossy file compression used with image files which relies on the inability of the human eye to distinguish certain colour changes and hues

Question 31

Define run length encoding (RLE)

Answer 31

A lossless file compression technique used to reduce the size of text and photo files in particular