Guan (官) or Mandarin is a group of Chinese varieties spoken in northern and southwestern China. This group includes Standard Mandarin or Standard Chinese, as well as regional varieties of Mandarin, and Dungan. As most varieties of Mandarin are found in northern China, they are also known as 北方话 [北方話] (běifānghuà) or "northern speech".
There are differences between the varieties of Mandarin from northern and southern China, particularly in the tones, and mutually intelligiblity between them is relatively low, however the differences are not as great as those between other varieties of Chinese.
Standard Mandarin developed from the language used by Chinese officials, most of whom came from Beijing. As a result, Standard Mandarin is based mainly on northern varieties of Mandarin, especially Beijing varieties. The officials called their language 官话 [官話] (guānyŭ) or "official language". The word Mandarin comes from Portuguese mandarim, from Malay menteri (minister), from Hindi मंत्री (mantrī - secretary), from Sanskrit मन्त्रिन् (mantrin - counselor, minster), and originally meant an official of the Chinese empire.
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Information about Guan / Mandarin
http://en.wikipedia.org/wiki/Mandarin_Chinese
http://en.wikipedia.org/wiki/Beijing_dialect
Mandarin lessons and courses
http://www.csulb.edu/~txie/ccol/content.htm
http://www.chineseon.net
http://www.csulb.edu/~txie/online.htm
http://www.languageguide.org/mandarin/
http://www.chinawestexchange.com/Mandarin/
http://www.chinese-outpost.com/language/
http://learnchinese.elanguageschool.net
http://www.chinese-lessons.com/mandarin/
http://langhub.com
http://www.mandarinlearn.com
http://www.learnchineseeveryday.com
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