Halfwidth and Fullwidth Forms is a Unicode block U+FF00–FFEF, provided so that older encodings containing both halfwidth and fullwidth characters can have lossless translation to/from Unicode.
[4] Range U+FF01–FF5E reproduces the characters of ASCII 21 to 7E as fullwidth forms.
The range U+FFA0–FFDC encodes halfwidth forms of compatibility jamo characters for Hangul, in a transposition of their 1974 standard layout.
The block has variation sequences defined for East Asian punctuation positional variants.
[10][9] The following Unicode-related documents record the purpose and process of defining specific characters in the Halfwidth and Fullwidth Forms block: