Side view of a carpenter ant. One good way to differentiate an ant from a termite is to look at the antennae. If they are "elbowed" or bent in the middle, as in this image, it's an ant. If you have something that looks like an ant but has straight antennae, more likely it's a termite.

antCamponotus pennsylvanicusFormicidaeHymenopteraantennaeanteriorcarpenter anteye