This property defines the Unicodes which belongs to Halfwidth and Fullwidth Forms block
Characters like !,",#, etc. are listed under Halfwidth and Fullwidth Forms Block.
233 Characters are present in Halfwidth and Fullwidth Forms Block starting with the Unicode point U+FF01 that represents the character !.
Currently, as per latest version 15.0.0, Unicode supports 328 number of Block. Here are a few examples - Latin Extended E,Adlam,Aegean Numbers, etc.