Jointed appendages are an advantage because they allow for any activity that requires movement, including walking, swimming, feeding, and defense. Jointed appendages act the same as a system of levers or like the joints on the human body.
Arthropods have jointed appendages, and the name "arthropod" means jointed foot. These invertebrate animals have a tough exoskeleton along with a segmented body and jointed appendages that allow for easy movement. The joints of jointed appendages are the same in all arthropods. They only bend in one direction, but they allow for complete mobility, and they may also be modified for special functions depending on the insect.