An arthropod is a class of animals from the invertebrate group. Mostly all insects belong to this class of animals. Insects are a class of arthropods. They constantly interact with the human life, either as pests or as beneficial organisms. In addition, there are some insect species that are an important component of the ecosystems. Since insects can tolerate adverse environmental conditions, they are widely distributed all over the world.

A Pest is a harmful animal. It can be from so many classes of animals, both invertebrate or vertebrate. Pests may include some insects, but also includes plants, other non-insect arthropods, and even single celled organisms and fungi. A pest, simply defined is an organism that attacks and causes damage to crops, persons, or property.