Producers make their own food, usually with sunlight. Trees and grass are producers.

Consumers do not make their own food. They eat producers or other consumers. Mice and hawks are consumers.

Decomposers break down dead producers and consumers. Mushrooms and many bacteria are decomposers.

The diagram on the left is a food chain. The arrows track the flow of energy.

Wheat uses energy from the Sun. Mice use wheat for energy. Hawks use mice for energy.

A food web is many interacting food chains.