Digital Data

Question 1

What is Data?

Answer 1

Unprocessed facts or figures that, on their own, have no meaning

Question 2

What is information?

Answer 2

When data is entered into a computer system and is processed, it becomes information, or ‘data with meaning’

Question 3

In what format does the computer store data?

Answer 3

Binary Format

Question 4

1 nibble = ?

Answer 4

4 bits

Question 5

1 byte = ?

Answer 5

8 bits

Question 6

1 kilobyte= ?

Answer 6

1024 bytes

Question 7

1 megabyte= ?

Answer 7

1024 kilobytes

Question 8

1024 megabytes=?

Answer 8

1 Gigabyte

Question 9

1024 Gigabytes=?

Answer 9

1 Terabyte

Question 10

What is the Data type numeric

Answer 10

An integer number that can be positive or negative

An integer number that has no decimal or fractional parts

Question 11

Explain the Data type Date/Time

Answer 11

Long date: displayed as Sunday, April 1, 2018.

Medium date: displayed as dd-mmm-yyyy, e.g. 1-Apr-2018.

Short date: displayed as dd/mm/yyyy, e.g. 01/04/2018.

Long time: displayed as HH:MM:SS, e.g. 13:26:34

Medium time: displayed as HH:MM PM/AM, e.g. 01:26 PM

Short time: displayed as HH:MM, e.g. 13:26

Question 12

Explain the Data type Character/String

Answer 12

A character is a single letter or digit represented by the codes from the character set.

A string is textual data in the form of a sequence of characters.

Question 13

What is a pixel?

Answer 13

A smallest unit of a digital image that can be displayed and edited on a computer screen

Question 14

What is Image resolution

Answer 14

Represents the quality of an image
More pixels = higher quality

Question 15

What is a Bitmap Image?

Answer 15

Made up of Pixels

Stores details about every pixel on the image

Question 16

Advantage of Bitmap

Answer 16

Can be compressed which reduces file size

Question 17

Disadvantage of Bitmap

Answer 17

Storing every pixel means that file size is large

Question 18

What is a vector image?

Answer 18

stores information about the components that make up a image

Question 19

What is Streaming?

Answer 19

Streaming allows a video to be viewed on a website without needed to download it

Question 20

What is Buffer?

Answer 20

When the user if watching a part of a video, a buffer is used to download the next part of the video

Question 21

What is sample rate?

Answer 21

Number of audio sample captured per second to represent the sounds digitally

Question 22

What is Bit depth?

Answer 22

The number of bits used for each sound sample

Question 23

What is Bit rate?

Answer 23

The quantity of data measured in bits that is processed in a given amount of time.

Question 24

Explain Analogue to Digital Conversion

Answer 24

An analogue signal is a continuous varying signal that represents a physical quantity.

An analogue to digital converter (ADC) will sample a signal at regular time intervals.

Samples are then converted to digital format.

The frequency at which samples are taken is known as the sample rate, measured in Hertz (Hz).

Question 25

What is Data Portability

Answer 25

Data portability is the ability to transfer data from one computer to another or from one software application to another without having to re-enter the data.

Question 26

Expand JPEG

Answer 26

Joint Photographic Expert Group

Question 27

Expand TIFF

Answer 27

Tagged Image File Format

Question 28

Expand PNG

Answer 28

Portable Network Graphics

Question 29

Expand GIF

Answer 29

Graphic Interchange Format

Question 30

Expand CSV

Answer 30

Comma -separated-value

Question 31

Expand RTF

Answer 31

Rich Text Format

Question 32

Expand MIDI

Answer 32

Musical Instrument Digital Interface

Question 33

Expand MPEG

Answer 33

Moving Picture Experts Group

Question 34

Expand AVI

Answer 34

Audio Video Interleaved

Question 35

Expand PDF

Answer 35

Portable Document Format

Question 36

Expand WAV

Answer 36

Waveform Audio File

Question 37

Expand WMA

Answer 37

Windows Media Audio

Question 38

Explain Data Compression

Answer 38

Data compression Used to convert digital data to as small a size as possible while still maintaining the quality of the data contained in the file; allows data to be sent over the internet with acceptable transmission speeds

Question 39

Explain Lossy Compression

Answer 39

Reduces the file size by removing some data, such as reducing the number of colours used in an image.

Question 40

Explain Lossless Compression

Answer 40

Maintains the quality of the file, therefore no data is lost.