This chapter will provide an overview of research on the varieties of Chinese, namely, the traditional Chinese perspective on the unity of its linguistic identity and the one rooted in the Western tradition, which claims that the varieties of Chinese are a family of Sinitic languages. The term 方言 fāngyán ‘dialect’ will be discussed, along with the Western perception of the term. Extralinguistic factors such as Chinese identity, a common writing system and a shared history will help to explain why Chinese is so unique that it is considered by some to be a single language, despite its diversity.