Chinese characters, also called Hanzi, are logograms developed for the writing of Chinese. They have been adapted to write other East Asian languages, and remain a key component of the Japanese writing system where they are known as kanji. Chinese characters are the oldest continuously used system of writing in the world. By virtue of their widespread current use in East Asia, and historic use throughout the Sinosphere, Chinese characters are among the most widely adopted writing systems in the world by number of users.