Decapoda is an order of crustaceans that includes familiar species such as crabs, lobsters, and shrimp. The name "Decapoda" means "ten-footed," referring to the ten limbs that these animals typically possess. They are found in various aquatic environments, from oceans to freshwater habitats. Members of the Decapoda have a hard exoskeleton and are known for their diverse shapes and sizes. They play essential roles in ecosystems as both predators and prey, contributing to the food web. Many species are also important for human consumption and are harvested in commercial fisheries.