ASCII established the foundation for text representation in computers.
Character ranges
- 0-31: Control characters (newline, tab, escape).
- 32-47: Punctuation and symbols (space, !, ", #, $, %, &).
- 48-57: Digits (0-9).
- 58-64: More punctuation (: ; < = > ? @).
- 65-90: Uppercase letters (A-Z).
- 91-96: Brackets and symbols ([ \ ] ^ _ `).
- 97-122: Lowercase letters (a-z).
- 123-127: More symbols ({ | } ~, DEL).
Extended ASCII
- 8-bit encoding (256 characters).
- Includes accented characters and symbols.
- Not standardized (many code pages exist).
Successors
- UTF-8: Backward compatible with ASCII, supports all Unicode.
- UTF-16: Used in Windows and Java.
- Latin-1 (ISO-8859-1): First 256 Unicode characters.
Common uses
- Text files and protocols.
- Programming language source code.
- Network communication.
- Command-line interfaces.
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