The basic difference between plants and animals is that plants make their own food, while animals obtain food from their environment. Because plants make their own food, they are called producers. Animals are known as consumers. They gather and consume organic material rather than making it themselves. Omnivores are animals that eat both plants and other animals.
Scavengers eat all the leftovers and other dead organisms.
No matter what an animal eats, all of its food can be traced back to the ability of plants to produce organic materials from the sun.