This property defines the Unicodes which have Katakana script
Characters like ァ,ア,ィ, etc. are listed under Katakana Script.
321 Characters are present in Katakana Script starting with the Unicode point U+30A1 that represents the character ァ.
Currently, as per latest version 15.0.0, Unicode supports 164 number of Script. Here are a few examples - Adlam,Ahom,Anatolian Hieroglyphs, etc.