Whales and dolphins communicate underwater by making different sounds that include chirps, clicks, barks, moans, yaps, squeaks, mews and whistles. It is not known whether dolphins and whales communicate with one another through these sounds or only communicate within their own species.
It is thought that each dolphin has its own whistle that acts as its name when dolphins are communicating with one another. The clicking noises that whales and dolphins make are not used exclusively for communication, however, as they are also used for echolocation. Echolocation is the process of bouncing sound off of objects in order to understand where objects are as well as where predators and other dolphins or other whales are located.