Chinese or the Sinitic language(s) (汉语/漢語, Pinyin: Hànyǔ; 华语/華語, Huáyǔ; or 中文, Zhōngwén) can be considered a language or language family. Originally the indigenous languages spoken by the Han Chinese in China, it forms one of the two branches of Sino-Tibetan family of languages. About one-fifth of the world’s population, or over 1 billion people, speak some form of Chinese as their native language. The identification of the varieties of Chinese as "languages" or "dialects" is controversial. As a language family Chinese has nearly 1.2 billion speakers; Mandarin Chinese alone has around 850 million native speakers, outnumbering any other languages in the world.

Spoken Chinese is distinguished by its high level of internal diversity, though all spoken varieties of Chinese are tonal and analytic. There are between six and twelve main regional groups of Chinese (depending on classification scheme), of which the most populous (by far) is Mandarin (c. 850 million), followed by Wu (c. 90 million) and Cantonese (c. 80 million). Most of these groups are mutually unintelligible, though some, like Xiang and the Southwest Mandarin dialects, may share common terms and some degree of intelligibility. Chinese is classified as a macrolanguage with 13 sub-languages in ISO 639-3, though the identification of the varieties of Chinese as multiple "languages" or as "dialects" of a single language is a contentious issue.

The standardized form of spoken Chinese is Standard Mandarin, based on the Beijing dialect. Standard Mandarin is the official language of the People's Republic of China and the Republic of China (Taiwan), as well as one of four official languages of Singapore. Chinese—de facto, Standard Mandarin—is one of the six official languages of the United Nations. Of the other varieties, Standard Cantonese is common and influential in Cantonese speaking overseas communities, and remains one of the official languages of Hong Kong (together with English) and of Macau (together with Portuguese).

From: wikipedia - Chinese language