Use this tag for questions related to Unicode Escapes, a Unicode character Escape sequence represents a Unicode character.
Quoting the MSDN page:
A Unicode escape sequence represents the single Unicode character formed by the hexadecimal number following the "\u" or "\U" characters. Since C# uses a 16-bit encoding of Unicode code points in characters and string values, a Unicode character in the range U+10000 to U+10FFFF is not permitted in a character literal and is represented using a Unicode surrogate pair in a string literal. Unicode characters with code points above 0x10FFFF are not supported.
Notice that unicode-escapes is used in its general meaning, thus you are encouraged to tag your question with the corresponding programming environment as well.
