Kanazukai

Kanazukai (仮名遣^?, "kana usage/use") are the orthographic rules for spelling Japanese in kana. All phonographic systems (of which kana is an example) attempt to account accurately the pronunciation in their spellings. However, pronunciation and accents change over time and phonemic distinctions are often lost. Various systems of kanazukai were introduced to deal with the disparity between the written and spoken versions of Japanese.

The former mainstream kana usage, or the Kyū-Kanazukai (旧仮名遣, "old kanazukai"), is based on classical texts, especially man'yōgana. Created by Keichū in the early Edo period, it is also known as the Keichū Kanazukai. It was the mainstream kanazukai until the Gendai Kanazukai was introduced in 1946.

There were other minor systems throughout history that are now defunct:

Derived from the Kyū-Kanazukai, it is a revision to better approximate modern pronunciation that is still used currently. As an adaption of the Kyū-Kanazukai, it is still not entirely phonetic, especially in respect to long vowels and particles.

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