It is the norm to divide dialects is into seven main ones, with the understanding that many others can exist in remote areas. Whether they are separate languages, or dialects or regional accents is a matter of socio-linguistics, involving political and cultural identities as well as speech. They are often said to be about as distinct as the Romance languages are, one from the other. Spanish and Italian, for example, may be mutually intelligible at some simple level, but Romanian and, say, Galician probably are not. The same is true for the divisions within the Chinese family of languages. The people of China, however, feel themselves part of the same cultural and national heritage, and therefore, refer to all the variations in their speech as dialects of a common tongue.
Chinese has one term for the unified system of writing: 中文 Zhōngwén. The spoken word is usually referred to as 汉语 or 漢語 Hànyǔ, the language of the Han Chinese. The single ethos and nationality of the Han Chinese comes from the cultural unification of the Han dynasty (200 BCE to 200 CE), providing a common cultural heritage in Classical Chinese.
Inside the People'ss Republic of China and also in Singapore, the government uses Standard Mandarin for all official purposes and calls all the other dialects 方言 fāngyán (regional tongues).
The map below shows where the different dialects of Chinese are spoken. These seven main dialects are as follows:
Guān (Standard Mandarin) 北方话 or 北方話 běifānghuà (northern dialect) and also 官话 or 官話 guānhuà (government dialect) is spoken by 850 million people world wide.Wú (吳 or 吴) is the language of Jiangsu Province and the Shanghai area, and is spoken by 90 million people.
Yuè(Cantonese) 粵 or 粤 is spoken in Guangdong (Canton area) and in Hong Kong, totaling 80 million people.
Mǐn 閩 or 闽 of Fujian province, also includes Taiwanese local language, and is spoken by 50 million people. Xiāng 湘 is the language of 35 million people.
Kèjiā (Hakka) 客家 or 客 is also spoken by about 35 million.
Gàn (Jiangxi) 贛 or 赣 is a dialect spoken by around 20 million inhabitants of China.
Sub-dialects have been identified as offshoots of a dominant language strain, including Jìn 晋 or 晉 from Mandarin (32 million), Huī 徽 from Wu (3.2 million), and Píng 平话 or 平話from Cantonese, at least in part (2 million).
A few other smaller groups are also recognized, like: Danzhou dialect (in Danzhou, on Hainan Island), Xianghua (乡话 ) (different from Xiang (湘 )), which is a dialect in the western part of Hunan province, and Shaozhou Tuhua, a dialect in the northern districts of Guangdong. Also considered a Chinese-like language is Dungan, a tongue of Central Asia, written in Cyrillic and not spoken within China's borders; however, it is considered a close relative of Mandarin.
A recognized non-profit organization now known as SIL International publishes a respected catalogue and census of the world's languages, called "Ethnologue: Languages of the World." According to Ethnologue, fourteen distinct dialects of Chinese have been identified: the core 7, the derivative 3, and the 4 additional ones, as mentioned above.