Very brief history of Japanese

Nobody is quite sure how Japanese originated as a spoken language, but genetic studies show there have been multiple human migrations from several places in Asia, including China. Sentence structure and use of honourifics, for example, is also observed in Korean. At any rate, Chinese written language was introduced around the year 500 and was sometimes used phonetically, leading to the Chinese logograms -- now called Kanji, which represent ideas rather than sounds -- being read aloud differently in Japan than in China. In the following centuries, Kanji were modified to represent distinct sounds. These characters are called Kana, and there exist two sets of them: Katakana, which was used by men in official business; and Hiragana, which was developed as an alternative for women, because, go figure, women also had a need to write.

Modern, written Japanese is no longer distinguished by gender and mixes Kanji, Katakana and Hiragana fluidly, although there are conventions about which types of words are written with which writing system.