Coriander can come in seed form, powdered form, the leaves,. and the stalks are also important in Asian dishes. All from one plant known to us as coriander and to Nth Americans and those in the zone as cilantro.
ETA; My intention was to show richard198 that HE is not totally correct as he was quick to point out to others, and getting facts right is a good thing. I certainly do not intend to enter into an online B session tho'! lol
ETA:
http://en.wikipedia.org/wiki/Coriander