About 4000 species have been described, but only 1% of them are considered to be pests. Most of them are found on tropical rain forest floor for decaying leaves, under bark, in caves and holes in the ground, etc. Most of them The cockroaches we know are domicile pests or pests in places that sell food. Fossil evidence shows that cockroaches have been around for over 300 million years, but their body shape has changed only slightly since then.

Depending on the species, adult cockroaches range in size from 2-80mm long. Like any other insect, the cockroach has three body parts: head, thorax and abdomen. There is a pair of tentacles, a pair of large eyes, and a mouth section that chews on the head. At the thorax, there are two pairs of legs and two pairs of wings (except the Harlequin cockroach which has no wings).