Kanji is kind of an ideograph, which is developed from a pictograph. Actually there are 45,000 letters of Kanji in Japan. It says a normal university graduate knows about 8,000 letters.

At least 2,000 letters (as junior high graduate) is necessary to live well in Japan. The Kanji which learn until university graduation are the basic for social life. It says a Japanese learn how to read around 20,000 Kanji in the life. But writing is another matter.

Lately, by the development of computer technology, there is less chance to write Kanji in our life. Actually, I forget how to right sometimes.