Pinyin is the official romanization system of Chinese. It is supplementary to the 5,000 year old traditional Chinese writing system.
How is it used?
pronunciation tool for language learners (children, foreigners, speakers of other Chinese dialects)
in index systems (library catalogues, dictionaries etc.)
for inputting Chinese characters into a computer
names (people, places etc) in China
in the nonChinese media - for names (e.g. Beijing, Mao Zedong, rather than Peking and Mao Tse Tung as used earlier). Tone marks are always left off except when pinyin is used in Mandarin textbooks.
How is pinyin written?
The pinyin system uses the standard Western alphabet. Pinyin takes the traditional Chinese analysis of the Chinese syllable into:
initials
finals
tones
as its point of departure.
How is pinyin pronounced?
This is the same as asking " What Chinese sounds do the pinyin symbols stand for"? Mandarin has consonant sounds that are found in most of the world's languages. For example,
labial sounds: b, p, m, f,
dental sounds d, t, n, l,
velar sounds g, k, h are quite close to English.
On the other hand,
retroflex sounds: zh, ch, sh, r
palatal sounds: j, q, x
dental sounds z, c, s
may require extra effort from the learner for two reasons.
they are difficult to pronounce for speakers of English and many other languages because they represent sounds that are less common in the world's languages.
the symbols (except for s) are misleading for learners because they tend to associate them with English sounds.