The order has three families: Alligatoridae, Crocodylidae, and Gavialidae. Alligators and caimans are in the alligator family; crocodiles are in the crocodile family; and the Indian gharial is in the gavial family.The differences among them seem pretty small, compared to the differences among members of, say, the carnivores.est Answer: Crocodiles typically thrive in saltwater environments and are very aggressive when in comparison to alligators and caimans. Also, the teeth of a croc are visible even when the mouth is closed. Crocodiles also have stubbier, stouter snouts that alligators.