Emoji-specific variation selectors
Variation Selectors is a Unicode block containing 16 Variation Selector format characters (designated VS1 through VS16). They are used to specify a specific glyph variant for a Unicode character. They are currently used to specify standardized variation sequences for mathematical symbols 27C0–27EF , symbols, 'Phags-pa A840–A87F letters, and CJK unified ideographs 4E00–9FFF corresponding to CJK compatibility ideographs F900–FAFF . At present only standardized variation sequences with VS1, VS15 and VS16 have been defined.