Mollusks are a large group of invertebrate animals that include oysters (6 letters), clams (4 letters), conchs (5 letters), chitons (6 letters), and pteropods (8 letters). They are characterized by their soft bodies, which are usually protected by a hard shell. Oysters are bivalve mollusks that live in saltwater and freshwater habitats. Clams are also bivalve mollusks that live in both marine and freshwater environments. Conchs are large sea snails with a spiral shell. Chitons are small mollusks with eight overlapping plates on their shells. Pteropods are small, free-swimming mollusks with a pair of wing-like structures.