This document discusses insect development and metamorphosis. It describes two types of development: incomplete and complete. Incomplete development involves nymphs that resemble wingless adults, while complete development involves distinct larval, pupal, and adult stages. The document outlines characteristics of orders that undergo complete metamorphosis, including Neuroptera, Lepidoptera, Hymenoptera, Diptera, and Coleoptera. It provides diagnostic traits for identifying immature stages of these orders.