Kana is a general term for the syllabic Japanese scripts hiragana (ひらがな) and katakana (カタカナ) as well as the old system known as man'yōgana. These were developed from the logographic characters of Chinese origin known in Japan as Kanji ( ; Chinese pronunciation "hànzì"), as an alternative and adjunct to these latter.

In addition, kana were borrowed into Taiwanese to indicate the pronunciation of Chinese characters like furigana during the Japanese occupation of Taiwan. See Taiwanese kana.

• Neither Hiragana nor Katakana have kana to represent ye, yi or wu sounds. However, ye is believed to have existed as a syllable in pre-Classical Japanese (prior to the advent of kana), and is generally represented (for purposes of reconstruction) by the kanji 江. In later periods, the syllable we (represented by the katakana ヱ and hiragana ゑ) came to be realized as 1, as demonstrated in 1600s-era European sources, but later merged with the vowel e and was eliminated from official orthography in 1946. "Ye" in modern orthography is commonly represented using いぇ or イェ.
• While no longer a part of standard orthography, both wi and we are still sometimes used stylistically, such as in ウヰスキー for "whiskey," and ヱビス for Yebisu, a beer brand.

Modern usage

Hiragana is mostly used to indicate prefixes, particles, and grammatical word endings (okurigana). It is also used to represent entire words (usually of Japanese, rather than Chinese, origin) in place of kanji. See the article hiragana for details.

Today katakana is most commonly used to write words of foreign origin that do not have kanji representations. For example, "George W. Bush" can be expressed as ジョージ・W・ブッシュ. Katakana is also used to represent onomatopoeia, technical and scientific terms, and some corporate branding. See the article katakana for details.

Kana can be written in small form above or next to lesser-known kanji in order to show pronunciation; this is called furigana. Furigana is used most widely in children's books. Literature for young children who do not yet know kanji may dispense with it altogether and instead use hiragana combined with spaces.

History

Both hiragana and katakana developed from the ancient kana system man'yōgana, a kind of phonetic characters using kanji. Man'yōshū, a poetry anthology assembled in 759, is written in this early script.

Kana is traditionally said to have been invented by the Buddhist priest Kūkai in the 9th century. Kūkai certainly brought the Siddham script home on his return from China in 806; his interest in the sacred aspects of speech and writing led him to the conclusion that Japanese would be better represented by a phonetic alphabet than by the kanji which had been used up to that point.