Shrimp have five pairs of jointed legs on the thorax used for walking and five pairs of swimming legs. A shrimp also has three pairs of feeding appendages.
In addition to the 16 appendages, shrimp have two pairs of sensory antennae, a tail fan and compound eyes. Shrimp are invertebrates with a hard exoskeleton. As a shrimp grows, it sheds its exoskeleton to make a new one. Shrimp are omnivores; they eat plant material and small animals. Shrimp are part of the class Crustacea along with crayfish, crabs, lobsters and the trilobite, which became extinct around 245 million years ago.