1.3 Data Storage and Compression

Question 1

What are the 9 units of measuring data?

Answer 1

Bit
Nibble
Byte
Kibibyte
Mebibyte
Gibibyte
Tebibyte
Pebibyte
Exbibyte

Question 2

How Bits many are in a nibble?

Answer 2

4

Question 3

How Bits many are in a Byte?

Answer 3

8

Question 4

From Kibibyte to Exbibyte what is the amount needed to reach the next unit?

E.g. kibibyte to Mebibyte

Answer 4

1024 needed for every step

Question 5

What does Compression do?

Answer 5

Compression exists to reduce the size of the file

Question 6

Name all four benefits of compressing a file.

Answer 6

1. not as much storage space needed to store the file
2. it will take less time to transmit the file from one device to another
3. it will be quicker to upload and download the file
4. Not as much bandwidth is needed to transmit the file over the internet

Question 7

What are the two types of compression?

Answer 7

lossy and lossless

Question 7

What is the difference between how lossy and lossless compress data?

Answer 7

lossy reduces file size by PERMANENTLY removing data while lossless reduces file size by TEMPORARILY altering the data

Question 8

What are some examples of unnecessary data that lossy can remove in an image file?

Answer 8

Unnecessary data that is removed are colors the eye cannot distinguish. This means that a lossy compression algorithm for an image file could reduce the size of the file by reducing the color depth. It could also reduce the size of the file by reducing the image resolution, reducing the number of pixels used to create the image

Question 9

What is perceptual music shaping?

Answer 9

a process that is used in lossy compression that removes sound that cannot be normally heard by the human ear

Question 10

What is run-length encoding (RLE)?

Answer 10

run-length encoding (RLE) is an algorithm that groups together repeating patterns and indexes them