A food web is a network of interrelated and interconnected food chains that include producers, consumers, and decomposers. It depicts various feeding relationships that exist between different species within an ecosystem. A food chain is a network of links in a food web, where the producers are consumed by the predators-primary and secondary consumers and then the detritivores and finally by decomposers. When many such individual food chains occur in an ecosystem, it is known as a food web.

Organisms in food webs are grouped into categories called trophic levels. Roughly speaking, these levels are divided into producers (first trophic level), consumers, and decomposers (last trophic level) . Producers are the organisms that produce their food, such as plants, and they form the base of the food web. Primary consumers are herbivores that eat producers or plants, while secondary consumers are carnivores that eat primary consumers. Tertiary consumers are carnivores that eat secondary consumers.

A food web is more realistic than a food chain, as it consists of various food chains interlinked at different trophic levels. It is not straight, and the food chain components do not run parallel. Food webs provide several alternate foods to the consumers, and there are feedback checks that operate in a food web that keeps the populations of various species constant. A food web is essential for the stability of an ecosystem.