Are all Japanese characters in common use included in Unicode?
Well, until recently the Unicode Consortium’s own FAQ answered this question ‘no’, although as of 2003 it has been changed. However, it depends on the definition of ‘common use’. The number of kanji in common religious use, for instance, is extremely high and extends beyond the Unicode repertoire, because the sutras are studded with peculiar characters. It is also possible to find several placenames that are normally represented by characters or distinct variants not found in Unicode, and abbreviated or informal shapes found on shop signs are absent too; this site contains evidence of several such forms. On the other hand, if by ‘common use’ you mean things that people are actually likely to have to write down on a daily basis, then in practise Unicode would normally be found to contain them all. A special issue is the hentaigana, old intermediate forms between kanji and modern-day kana, vital in cursive calligraphy (sousho). These are absent from Unicode (and it would be very complica
