The currency in circulation is as follows:
100 RMB: two types although only one is in common circulation. The maximum denomination note. Equivalent to about $13 US (subject to the current exchange rate). The older style is blue (picture coming soon) and is pretty much gone but is still valid currency.
50 RMB: two types, both in common usage, newer type is pictured on the left. The older, yellow type is larger and proved a significant target with currency forgers but this style is dying out slowly.
20 RMB: one type circulating
10 RMB: two types circulating. The older one to the right (picture coming soon).
5 RMB: two types circulating. The left style is the newer, harder to fake version. It is slightly smaller than old one.
2 RMB: one type circulating.
1 RMB: note and coin. The 1 RMB coin is fairly large, about 2cm and heavier than all other coins.
5 Jiao (0.5 RMB): note and coin. The 5 Jiao coin is fairly small and is easily recognizable as the only bronze colored coin in the Chinese currency system.
2 Jiao (0.2 RMB): note. As with the 5 Jiao note is smaller than the 1 RMB note by about 15%. The 5, 2, and 1 Jiao notes are all pretty much this size.
1 Jiao (0.1 RMB): note and coins.