An organism that eats producers or other organisms for energy is called a consumer. The three main types of consumers are herbivores, carnivores and omnivores.
In an ecosystem, primary producers are the plants and other organisms that are able to make their own food. Herbivores eat primary producers, so they are known as plant-eating organisms. Deer and cows are examples of herbivores.
Carnivores, also called secondary consumers, eat herbivores and other carnivores. Lions are classified as carnivores because they feed on other animals. Omnivores eat plants and animals. The raccoon is a good example of an omnivore because it eats vegetables as well as fish and mice.