Before the 5th century, the Japanese had no writing system of their own. They began to adopt the Chinese writing script along with many other aspects of Chinese culture after their introduction by Korean monks and scholars during the 5th and 6th centuries AD.
At first, the Japanese wrote in Classical Chinese, with Japanese names represented by characters used for their meanings and not their sounds. Later, this latter principle was used to write pure Japanese poetry and prose; however, some Japanese words were written with characters for their meaning and not the original Chinese sound. An example of this mixed style is the Kojiki, which was written in 712 AD. They then started to use Chinese characters to write Japanese in a style known as man'yōgana, a syllabic script which used Chinese characters for their sounds in order to transcribe the words of Japanese speech syllable by syllable.
Over time, a writing system evolved. Chinese characters (kanji) were used to write either words borrowed from Chinese, or Japanese words with the same or similar meanings. Chinese characters were also used to write grammatical elements, were simplified, and eventually became two syllabic scripts: hiragana and katakana.
Modern Japanese is written in a mixture of three main systems: kanji, characters of Chinese origin used to represent both Chinese loanwords into Japanese and a number of native Japanese morphemes; and two syllabaries: hiragana and katakana. The Latin alphabet is also sometimes used. Arabic numerals are much more common than the kanji characters when used in counting, but kanji numerals are still used in compounds, such as 統一 tōitsu ("unification").
Hiragana are used for words without kanji representation, for words no longer written in kanji, and also following kanji to show conjugational endings. Because of the way verbs (and adjectives) in Japanese are conjugated, kanji alone cannot fully convey Japanese tense and mood, as kanji cannot be subject to variation when written without losing its meaning. For this reason, hiragana are suffixed to the ends of kanji to show verb and adjective conjugations. Hiragana used in this way are called okurigana. Hiragana are also written in a superscript called furigana above or beside a kanji to show the proper reading. This is done to facilitate learning, as well as to clarify particularly old or obscure (or sometimes invented) readings.
Katakana, like hiragana, are a syllabary; katakana are primarily used to write foreign words, plant and animal names, and for emphasis. For example "Australia" has been adapted as Ōsutoraria, and "supermarket" has been adapted and shortened into sūpā. Rōmaji (ローマ字), literally "Roman letters," is the Japanese term for the Latin alphabet. Rōmaji are used for some loan words like "CD", "DVD", etc., and also for some Japanese creations like "Sony."
Japanese students begin to learn kanji characters from their first year at elementary school. A guideline created by the Japanese Ministry of Education, the list of kyōiku kanji, specifies the 1,006 simple characters a child is to learn by the end of sixth grade. Children continue to study another 939 characters in junior high school, covering in total 1,945 jōyō kanji ("common use kanji") characters, which is generally considered sufficient for everyday life, although many kanji used in everyday life are not included in the list. An appendix of 290 additional characters for names was decreed in 1951. Various semi-official bodies were set up to monitor and enforce restrictions on the use of kanji in the press, publishing, in television broadcasts, etc. Thereafter, the official list of kyōiku kanji was repeatedly revised, but the total number of officially sanctioned characters remained largely unchanged.
A different list of officially approved kanji is used for purposes of registering personal names. Names containing unapproved characters are denied registration. However, as with the list of kyōiku kanji, criteria for inclusion were often arbitrary and led to many common and popular characters being disapproved for use. Under popular pressure and following a court decision holding the exclusion of common characters unlawful, the list of "approved" characters was substantially extended. Furthermore, families whose names are not on these lists were permitted to continue using the older forms.
Historically, attempts to limit the number of kanji in use commenced in the mid-19th century, but did not become a matter of government intervention until after Japan's defeat in the Second World War. During the period of post-war occupation (and influenced by the views of some U.S. officials), various schemes including the complete abolition of kanji and exclusive use of rōmaji were considered. The kyōiku kanji scheme arose as a compromise solution.