Mandarin (/ˈmændərɪn/ MAN-dər-in; simplified Chinese: 官话; traditional Chinese: 官話; pinyin: Guānhuà; lit. 'officials' speech') is the largest branch of the Sinitic languages. Mandarin varieties are spoken by 70 percent of all Chinese speakers over a large geographical area that stretches from Yunnan in the southwest to Xinjiang in the northwest and Heilongjiang in the northeast. Its spread is generally attributed to the greater ease of travel and communication in the North China Plain compared to the more mountainous south, combined with the relatively recent spread of Mandarin to frontier areas.
Many varieties of Mandarin, such as those of the Southwest (including Sichuanese) and the Lower Yangtze, are not mutually intelligible with the Beijing dialect (or are only partially intelligible). Nevertheless, Mandarin as a group is often placed first in lists of languages by number of native speakers (with nearly one billion). Because Mandarin originated in North China and most Mandarin varieties are found in the north, the group is sometimes referred to as Northern Chinese (simplified Chinese: 北方话; traditional Chinese: 北方話; pinyin: Běifānghuà; lit. 'northern speech').