Characters

Question 1

What are alphanumeric characters used for?

Answer 1

To make words and strings (includes uppercase and lowercase letters, digits 0-9 and symbols (?,£,+)

Question 2

What are character sets?

Answer 2

Collections of characters that computer recognises from binary representation. They also contain special characters

Question 3

What are character sets used for?

Answer 3

Used as a way of converting characters to binary code and (vise versa) as computers are unable to process characters, only binary code. They use character sets to translate binary code into a particular character.

Question 4

What does pressing a button on your keyboard do?

Answer 4

It sends a binary signal to your computer telling it what key you pressed

Question 5

What is the number of bits you need based on?

Answer 5

The character set. Different character set have different amount of characters. The number of characters in the character set determines how many bits you need.

Question 6

What is ASCII?

Answer 6

ASCII is the most commonly used character set in the English speaking World.
Each ASCII character given 7 bit binary code to represent 128 characters (including all letters, numbers, symbols and commands
An extra bit (0) added to each ASCII character, so ASCII fits nicely into one byte.

Question 7

What is Unicode?

Answer 7

Coming in different forms, Unicode try’s to cover every possible letter or symbol that might be written. Unlike ASCII, Unicode used multiple bytes for each character
The first 128 codes are the same as ASCII

Question 8

What is the best thing about Unicode?

Answer 8

It covers all major languages, even those that use a completely different alphabet (Greek, Russian, Chinese).

Question 9

How is the size of text file calculated?

Answer 9

File size (in bits) = Number of bits per character x number of characters