Crustaceans are a fascinating group of arthropods that include lobsters, crabs, shrimp, and crayfish. Class Crustacea is a diverse and large group that can be further grouped into several categories based on their body shape, size, and function. Synonyms for Class Crustacea include "shellfish", "crabs and lobsters", "decapods", and "shrimps". These synonyms help to categorize and differentiate the varied species within the group. The fascinating Class Crustacea includes some of the ocean's most iconic and delicious creatures, which have been used for centuries in cuisine and greatly appreciated by seafood lovers worldwide.