- I think that only daring speculation can lead us further and not accumulation of facts. Albert Einstein
Between 5,000 and 10,000 characters, or kanji, are used in written Japanese. In 1981 in an effort to make it easier to read and write Japanese, the Japanese government introduced the 常用漢字表 (jōyō kanji hyō) or the "List of Chinese Characters for General Use", which includes 1,945 regular characters, plus additional characters used for people's names (人名用漢字 - jinmeiyô-kanji). This is based on the list of 1,850 regular use kanji (当用漢字 tôyô kanji) published in 1946. In 2010 an additional 196 commonly-used kanji were added to the jōyō kanji taking the total to 2,136.
Newpapers and other media and publications use mainly jōyō kanji and provide furigana (reading in kana) for non-jōyō kanji. Japanese children are expected to know all of the jōyō kanji by the end of high school but to read specialist publications and ordinary literature, they need to know another two or three thousand kanji.
The word kanji is the Japanese version of the Chinese word hànzì, which means "Han characters". Han refers to the Han Dynasty (206BC - 220AD) and is the name used by the Chinese for themselves.
When the Japanese adopted Chinese characters to write the Japanese language they also borrowed many Chinese words. Today about half the vocabulary of Japanese comes from Chinese and Japanese kanji are use to represent both Sino-Japanese words and native Japanese words with the same meaning.
For example, the native Japanese word for water is mizu while the Sino-Japanese word is sui. Both are written with the same character. The former is known as the kun yomi (Japanese reading) of the character while the latter is known as the on yomi (Chinese reading) of the character.