Insects are invertebrates that referred to as the class Insecta. They are the most numerous and most widespread terrestrial group within the phylum Arthropoda. They are the most diverse group of animals on the earth, with around 925,000 species identified.

 

Insects live in all environments on the planet. There are approximately 5,000 dragonfly species, 2,000 mantises, 20,000 grasshoppers, 170,000 butterflies and moths, 120,000 fly, 82,000 true bugs, 350,000 beetles, and 110,000 bee and ant species described to date. Adult modern insects range in size from 0.13 mm to 555 mm The study of insects is called entomology.