A lobster is a crustacean, or an animal covered with a hard shell. Lobsters live in the sea. There are about 225 kinds of lobsters in four families, true lobsters, spiny lobsters, slipper lobsters, and deep-sea lobsters. All lobsters have hand shells covering their bodies. As they grow, young lobsters molt, or shed their old shells and grow new ones. True lobsters and spiny lobsters are caught as food. True lobsters have large pinching claws. Spiny lobsters do not. Most lobsters are caught in baited traps.