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2. Notational conventions

RFC 2119 Key Words

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].

UCS Character Notation

UCS characters are designated by the U+HHHH notation, where HHHH is a string of from 4 to 6 hexadecimal digits representing the character number in ISO/IEC 10646.

Examples

  • U+0041 - Latin Capital Letter A
  • U+4F60 - CJK Unified Ideograph (你)
  • U+1F600 - Emoji (😀)