I’m going to talk about her origin. Although Japanese already had a developed oral language, it did not have a writing system own.
During the 5th, 6th and 7th centuries there was a cultural exchange between China and Japan. It was then that the Chinese writing system was transmitted to Japan. However the two languages remained separate, as the educated class wrote in Chinese. It was until the 8th and 9th centuries that the Chinese characters they began to adapt to Japanese speech.
As the Chinese writing system was very complex for the Japanese syntax, little by little the kana, writing systems that simplified some Chinese characters to facilitate and speed up their writing. At first thehiragana it was used exclusively by women. He katakana It was used by Buddhist priests as a mnemonic to facilitate the reading of Chinese texts.
It was in this way that the Japanese writing system was divided into three. On the one hand, it has a system of kanas which is divided into hiragana and katakana, and on the other hand, it has the kanji. Even though some characters of kanji they are similar or identical to the original Chinese characters, their pronunciation was adapted to the Japanese language, and they are different.