Insects (from Latin insectum) are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed legs, compound eyes and one pair of antennae

Insects have exoskeletons (skeletons on the outside). Their skeletons are made out of thin, hard pieces or plates, like armour, made of chitin. All together, these pieces make a hard layer around the insect’s body. The exoskeleton protects the insect. 

The body of an insect has three main parts: a head, a thorax, and an abdomen. On the head are an insect’s compound eyes, its two antennae (they feel and smell things), and its mouth. On the thorax, insects have wings and legs.