Japanese language and computers

In relation to the Japanese language and computers many adaptation issues arise, some unique to Japanese and others common to languages which have a very large number of characters. The number of characters needed in order to write English is very small, and thus it is possible to use only one byte to encode one English character. However, the number of characters in Japanese is much more than 256, and hence Japanese cannot be encoded using only one byte, and Japanese is thus encoded using two or more bytes, in a so-called "double byte" or "multi-byte" encoding. Some problems relate to transliteration and romanization, some to character encoding, and some to the input of Japanese text.

There are several standard methods to encode Japanese characters for use on a computer, including JIS, Shift-JIS, EUC, and Unicode. While mapping the set of kana is a simple matter, kanji has proven more difficult. Despite efforts, none of the encoding schemes have become the de facto standard, and multiple encoding standards are still in use today.

For example, most Japanese emails are in JIS encoding and web pages in Shift-JIS and yet mobile phones in Japan usually use some form of Extended Unix Code. If a program fails to determine the encoding scheme employed, it can cause mojibake (文字化け^?, "misconverted garbled/garbage characters", literally "transformed characters") and thus unreadable text on computers.

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