Cilantro and Coriander are pretty similar to each other but the main difference between Cilantro and Coriander is in the taste.
Coriander has a sweet, warm and toasty flavor to and Cilantro has more of a soapy taste to it and isn't as good as Coriander.
I would use Coriander in dishes that call for Cilantro because Cilantro doesn't really taste all that great while Coriander tastes much better.