Clams are animals that have soft bodies. The soft body is covered with a hard protective shell. Clams are found in many different places like lakes, streams, and on shores of the ocean. There are different kinds of clams like Soft-shell clams, Hard-shell clams, Asian clams and Giant clams. In many shells there is a shiny, smooth substance called mother-of-pearl. Most clams eat a food called plankton and other clams eat a small, shrimplike animal. The Giant clam can grow to be 4 feet in length.