 Their display forms were designed to fit into an approximately square array of pixels, hence the name "full-width".For backwards compatibility, separate support for half-width katakana has continued to be available in modern multi-byte encoding schemes such as Unicode, by having two separate blocks of characters – one displayed as usual (full-width) katakana, the other displayed as half-width katakana.Although often said to be obsolete, the half-width katakana are still used in many systems and encodings.