ASCII
Computer Science: OCR A Level, topic 4.1.21
American Standard Code for Information Interchange
The American Standard Code for Information Interchange (ASCII) character set is the most common character set.
ASCII
- Each character in ASCII is represented by a seven-bit binary code.
- That means there is a maximum of 128 characters.
- ASCII includes all commonly used letters and symbols in the English language.
7-bit letters?
- Each letter is represented by seven bits.
- This is useful because when used in an 8-bit system, the extra bit can be used as a check digit.
Limitations of ASCII
- 128 characters is perfectly fine for the English language. But it does not leave space for characters from other languages.
- An extended ASCII set was released which used all eight bits, but it was still not enough.
- This led to the release of Unicode.
Test yourself on ASCII
What is included in ASCII?
What is the main drawback of ASCII?