The currency of China is the Renminbi (RMB) (人民币). The Yuan (元) is the principle unit of the Renminbi. There are 10 Jiao (角) to the Yuan and 10 Fen (分) to the Jiao. However, for practical purposes, anything less than 5 Jiao (ie. half a Yuan) is useless.
Notes are issued in denominations of ¥1, ¥5, ¥20, ¥50 and ¥100. The highest denomination of ¥100 is equal to roughly US$14.60, €10, £9 and AU$15.80.
Approximate exchange rates are:
¥7 to US$1
¥10 to €1
¥11 to £1
¥6.5 to AU$1
There are also ¥0.1, ¥0.2 and ¥0.5 notes floating around from an older currency issue, but these are generally being replaced by coins. ¥1 coins are also common.
The Chinese Renminbi used to be pegged to the $US, but is now pegged to a basket of currencies and does fluctutate.