Data representation

Question 1

What is binary?

Answer 1

Representing numbers using base 2 (0s & 1s) – the only language that computers truly understand. 0 means off, 1 means on.

Question 2

What is denary?

Answer 2

Representing numbers using base 10 (0‐9) – these are our normal numbers that we use every day.

Question 3

What is hexadecimal?

Answer 3

Representing numbers using base 16 (0‐9 & A‐F). This language is never stored inside a computer, it is used for representing colours as it is easier for humans to interpret.

Question 4

What is binary addition?

Answer 4

Adding binary numbers together.

Question 5

What is a character?

Answer 5

A single letter, number or symbol (e.g., A, 1, !).

Question 6

What does ASCII stand for?

Answer 6

American Standard Code for Information Interchange.

Question 7

How many bits does ASCII use?

Answer 7

Uses 7 bits to store a maximum of 128 characters.

Question 8

What is Extended ASCII?

Answer 8

The same as ASCII, though uses 8 bits per character to represent 256 characters.

Question 9

What is Unicode?

Answer 9

A different form of character representation in a computer system, using 16 bits per character to allow 65,536 characters to be represented.

Question 10

What is an image in computing?

Answer 10

A picture that has been created or copied and stored in electronic form.

Question 11

What are pixels?

Answer 11

The individual units (dots) that make up an image.

Question 12

What is resolution in images?

Answer 12

The level of detail in an image (quality), measured in dots per inch (dpi).

Question 13

What is bit depth?

Answer 13

The number of binary digits used to represent each pixel in an image file.

Question 14

What is sampling?

Answer 14

Method of converting an analogue sound signal into a digital file containing binary numbers.

Question 15

What is sample rate?

Answer 15

The number of readings taken from a sound wave each second.

Question 16

What is compression?

Answer 16

The re‐encoding of data so that less bits are used to store it.

Question 17

What is lossy compression?

Answer 17

Removes data to reduce the size of a file (e.g., JPG).

Question 18

What is lossless compression?

Answer 18

Reorganises data to reduce the size of a file without removing any information (e.g., ZIP). No quality is lost.

Question 19

What are the binary place values for 1 byte?

Answer 19

• 128
• 64
• 32
• 16
• 8
• 4
• 2
• 1

Question 20

What are the binary place values for 1 nibble?

Answer 20

• 8
• 4
• 2
• 1

Question 21

What are the hexadecimal numbers from 0 to 15?

Answer 21

• 0
• 1
• 2
• 3
• 4
• 5
• 6
• 7
• 8
• 9
• A
• B
• C
• D
• E
• F

Question 22

What are the rules of binary addition for 0 + 0?

Answer 22

0

Question 23

What are the rules of binary addition for 1 + 0?

Answer 23

1

Question 24

What are the rules of binary addition for 0 + 1?

Answer 24

1

Question 25

What are the rules of binary addition for 1 + 1?

Answer 25

0, carry 1

Question 26

What are the rules of binary addition for 1 + 1 + 1?

Answer 26

1, carry 1

Question 27

What is a bit?

Answer 27

The smallest amount of data (stands for binary digit) (0 or 1).

Question 28

What is a nibble?

Answer 28

4 bits (Used for converting into hexadecimal).

Question 29

What is a byte (B)?

Answer 29

8 bits.

Question 30

What is a kilobyte (KB)?

Answer 30

1024 bytes.

Question 31

What is a megabyte (MB)?

Answer 31

1024 kilobytes.

Question 32

What is a gigabyte (GB)?

Answer 32

1024 megabytes.

Question 33

What is a terabyte (TB)?

Answer 33

1024 gigabytes.

Question 34

What is a petabyte (PB)?

Answer 34

1024 terabytes.

Question 35

What are common image file types?

Answer 35

* BMP * JPG * GIF * PNG * TIF

Question 36

What are common sound file types?

Answer 36

* MP3 * WAV * M4A

Question 37

What are common video file types?

Answer 37

* MP4 * WMV * MOV