Pill bugs, also known as roly-polies, are small, terrestrial crustaceans belonging to the order Isopoda. They are commonly found in gardens and damp environments, where they feed on decaying plant material. Unlike insects, pill bugs have a hard, segmented exoskeleton and can roll into a ball when threatened, which is how they get their nickname. These creatures are often mistaken for insects, but they are more closely related to crabs and shrimp. Pill bugs play an important role in the ecosystem by helping to decompose organic matter, enriching the soil as they break down dead plants and leaves.