Eating (also known as consuming) is the ingestion of food to provide for all organisms their nutritional or medicinal needs, particularly for energy and growth. Animals and other heterotrophs must eat in order to survive: carnivores eat other animals, herbivores eat plants, omnivores consume a mixture of both plant and animal matter, and detritivores eat detritus. Fungi digest organic matter outside of their bodies as opposed to animals that digest their food inside their bodies. For humans, eating is an activity of daily living.