While some insects and related organisms are pests that feed on plants in our yards, other insects and related organisms help keep these pests under control. Those that help us are referred to as beneficial insects or just beneficials .
Parasites are usually the immature stage of wasps and flies.
The adult wasp or fly lays an egg in or on the egg or immature stage of the pest. The developing parasite usually feeds inside the pest and slowly destroys it. Predators are usually larger than parasites. Predators actively seek and capture their prey. They either eat the whole prey or suck out its body contents.