Mollusks are a diverse group of soft-bodied animals that include creatures like snails, clams, and octopuses. They are known for their unique body structure, which typically includes a muscular foot for movement, a mantle that can produce a shell, and a visceral mass containing their organs. Mollusks can be found in various environments, from oceans to freshwater and even on land. These animals play important roles in ecosystems and human life. For example, oysters filter water and improve water quality, while squid and cuttlefish are popular seafood choices. Some mollusks, like snails, are also kept as pets or used in gardening to help with soil health.