Specials (Unicode block)

Unicode block containing some special codepoints and two non-characters / From Wikipedia, the free encyclopedia

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Specials is a short Unicode block of characters allocated at the very end of the Basic Multilingual Plane, at U+FFF0FFFF. Of these 16 code points, five have been assigned since Unicode 3.0:

  • U+FFF9 INTERLINEAR ANNOTATION ANCHOR, marks start of annotated text
  • U+FFFA INTERLINEAR ANNOTATION SEPARATOR, marks start of annotating character(s)
  • U+FFFB INTERLINEAR ANNOTATION TERMINATOR, marks end of annotation block
  • U+FFFC OBJECT REPLACEMENT CHARACTER, placeholder in the text for another unspecified object, for example in a compound document.
  • U+FFFD REPLACEMENT CHARACTER used to replace an unknown, unrecognised, or unrepresentable character
  • U+FFFE <noncharacter-FFFE> not a character.
  • U+FFFF <noncharacter-FFFF> not a character.
Quick facts: Specials, Range, Plane, Scripts, Assigned...
Specials
RangeU+FFF0..U+FFFF
(16 code points)
PlaneBMP
ScriptsCommon
Assigned5 code points
Unused9 reserved code points
2 non-characters
Unicode version history
1.0.0 (1991)1 (+1)
2.1 (1998)2 (+1)
3.0 (1999)5 (+3)
Unicode documentation
Code chart ∣ Web page
Note: [1][2]
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U+FFFE <noncharacter-FFFE> and U+FFFF <noncharacter-FFFF> are noncharacters, meaning they are reserved but do not cause ill-formed Unicode text. Versions of the Unicode standard from 3.1.0 to 6.3.0 claimed that these characters should never be interchanged, leading some applications to use them to guess text encoding by interpreting the presence of either as a sign that the text is not Unicode. However, Corrigendum #9 later specified that noncharacters are not illegal and so this method of checking text encoding is incorrect.[3]

Unicode's U+FEFF BYTE ORDER MARK character can be inserted at the beginning of a Unicode text to signal its endianness: a program reading such a text and encountering 0xFFFE would then know that it should switch the byte order for all the following characters.

Its block name in Unicode 1.0 was Special.[4]