Chinese characters (simplified Chinese: 汉字; traditional Chinese: 漢字; pinyin: hànzì; literally: 'Han characters') are logograms developed for the writing of Chinese. They have been adapted to write a number of other Asian languages. They remain a key component of the Japanese writing system (where they are known as kanji) and are occasionally and more so historically, used in the writing of Korean (where they are known as Hanja). They were formerly used for Vietnamese (in a system known as chữ Nôm) and Zhuang (in a system known as Sawndip). Collectively, they are known as CJK characters. Vietnamese is sometimes also included, making the abbreviation CJKV.