About

Unicode is the standard for computer representation of plain . It encompasses:

  • the Universal Character Set (UCS), intended to unambiguously represent all characters used in human writing systems in any language,
  • Unicode Transformation Formats (UTFs), defining standardized formats for storing and transmitting Unicode text, and
  • standards for processing and manipulating Unicode text.

The latest version is 6.0, published in 2011.

The Universal Character Set

Unicode assigns each character an integer code point (from 0 to 0x10FFFF) in the UCS to act as a unique reference. For example:

  • U+0041 A
  • U+0042 B
  • U+0043 C
  • ...
  • U+039B Λ
  • U+039C Μ

Unicode Transformation Formats

UTFs describe how to encode code points as byte representations. The most common forms are UTF-8 (which encodes code points as a sequence of one, two, three or four bytes) and UTF-16 (which encodes code points as two or four bytes).

Code Point          UTF-8           UTF-16 (big-endian)
U+0041              41              00 41
U+0042              42              00 42
U+0043              43              00 43
...
U+039B              CE 9B           03 9B
U+039C              CE 9C           03 9C

Specification

The Unicode Consortium also defines standards for sorting and collation algorithms, rules for capitalization, character normalization and other locale-sensitive character operations.

Identifying Characters

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