About Kanji
Kanji are the Chinese characters that are used in the modern Japanese logographic writing system along with hiragana, katakana, and the Arabic numerals. The Japanese term kanji literally means "Han characters"
History
Chinese characters first came to Japan on articles imported from China. An early instance of such an import was a gold seal given by the emperor of the Eastern Han Dynasty in 57 AD. It is not clear when Japanese people started to command Classical Chinese by themselves. The first Japanese documents were probably written by Chinese immigrants. For example, the diplomatic correspondence from King Bu of Wa to Emperor Shun of the Liu Song Dynasty in 478 has been praised for its skillful use of allusion. Later, groups of people called fuhito were organized under the monarch to read and write Classical Chinese. From the 6th century onwards, Chinese documents written in Japan tended to show interference from Japanese. This suggests the wide acceptance of Chinese characters in Japan.
When first introduced, texts were written in the Chinese language and would have been read as such. Over time, however, a system known as kanbun emerged, essentially using Chinese text with diacritical marks to allow Japanese speakers to read the characters in accordance with the rules of Japanese grammar.
The Japanese language itself had no written form at the time. A writing system called man'yogana (used in the ancient poetry anthology Man'yoshu) evolved that used a limited set of Chinese characters for their sound, rather than for their meaning.
Source: Wikipedia
Written Japanese uses three separate alphabets (four if you count "romaji", our standard 26-letter English alphabet). Hey, come back! It's not that bad; don't worry.
Two of the three are syllabic. They are called hiragana and katakana, and consist of fairly simple characters used to represent syllables. Hiragana and katakana are known collectively as "kana".
Kanji, however, are more complicated / difficult / beautiful / fascinating.
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