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 [BLOCK:miscellaneous-mathematical-symbols-a mathematical symbols], [BLOCK:emoticons-(emoji) emoji] symbols, [BLOCK:phags-pa 'Phags-pa] letters, and [BLOCK:cjk-unified-ideographs CJK unified ideographs] corresponding to [BLOCK:cjk-compatibility-ideographs CJK compatibility ideographs]. At present only standardized variation sequences with VS1, VS15 and VS16 have been defined.