Characters

Question 1

What are alphanumeric characters?

Answer 1

• used to make words and strings

- include upper and lower case letters, digits and symbols

Question 2

How can computers convert characters to binary code and vice versa?

Answer 2

Character sets

Question 3

What are character sets?

Answer 3

Collections of characters that a computer recognises from their binary representation.

Question 4

Character also contains what was well as alphanumerics?

Answer 4

Special characters which do certain commands like space, enter and delete.

Question 5

How does the computer use character sets to translate the binary code into a particular character?

Answer 5

When you press a button on your keyboard it sends a binary signal to the computer telling it which key you pressed, then the computer translates it using character sets.

Question 6

The number of bits you’ll need is based on what?

Answer 6

The character set

Question 7

What is an example of a standard character set?

Answer 7

ASCII, extended ASCII and unicode

Question 8

What is ASCII?

Answer 8

• most commonly used character set in the English speaking world
• each ASCII character is given a 7-bit binary code so can represent a total of 128 different characters.
• an extra 0 is added to the start of the binary code for each ASCII character, so each character can fit nicely into 1 byte.

Question 9

What is extended ASCII?

Answer 9

• character set which gives each character an 8-bit binary code, so a total of 256 different characters can be represented.
• The first 128 are in the exact same order as ASCII
• particularly useful for european languages like French and German which include accents on some of their vowels.

Question 10

What is unicode?

Answer 10

• comes in several different forms and tries to cover every possible character that might be written.
• most common forms is 16-bit and 32-bit binary codes.
• best thing is it covers all major languages even those who use a completely different alphabet like Greek, Russian and Chinese.