Insects and many other groups belong to the Phylum Arthropoda. This is a large group of invertebrate animals with the following principal characteristics:

1) A segmented body, segments are usually grouped into two or three distinct regions.

2) The appendages are paired and also segmented

3) Bilateral symmetry, where left and right sides of the body are essentially similar

4) An exoskeleton, a hardened outer covering periodically shed and renewed as the body grows