#CS250#Information#Computer-Science
Early Character Representation
- First instance of bit string representing text - Baudot Code (1870)
- Used for Morse Code
- 5 bits per character, so characters
- Character encodings chosen to put less strain on users
- In 1901, Donald Murray modifies it
- Introduces Carriage Return and Line Feed characters
- Now we can have multiple lines!
ASCII Character Representation
- 1963 American Standard Code for Information Interchange
- 7 bit code, 128 characters
- Adds digits, both letter cases and control characters
- Character encoding is redesigned for machine oriented criteria rather than human oriented criteria
- Makes sorting text by machine easier
- Alphabetic order = integer order of characters
- Changing case only requires changing one bit
- Upper and lower cases intentionally differ by 0x20
Unicode
- Unicode Consortium manages unicode
- Made by Xerox and Apple
- Up to 4 bytes per character
- Version 14.0 as of September 2021
- 144,697 characters
- Has other language characters and emoji! :)