Chapter 26 - Coding Systems

Question 1

What is a character code?

Answer 1

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

Question 2

Define ASCII

Answer 2

A standard binary coding system for characters and numbers

Question 3

Define Unicode

Answer 3

A standard binary coding system that has superseded ASCII

Question 4

What is parity bit?

Answer 4

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

Question 5

Describe even parity

Answer 5

The numbers of 1s in the code is counted.
If there is an odd number of 1s, the parity bit is set to one to make the total number of 1s even.
When the data is received, it is checked to ensure that there are still an even number of 1s.
If there are, then the data is assumed to be correct.

Question 6

What is majority voting?

Answer 6

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

Question 7

What is check digit?

Answer 7

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

Question 8

Define
1 - Bit-mapped graphics
2 - Pixel
3 - Resolution

Answer 8

1 -An image made up of individual pixels.

2 - An individual picture element

3 - width x height or pixels per inch

Question 9

What is colour depth?

Answer 9

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

Question 10

How do you work out storage for bit-mapping?

Answer 10

Resolution x colour depth

If you had 24 bits allocated that would give 2^24 combinations.

Question 11

Define vector graphics

Answer 11

A image made up of object and coordinates.