In the history of man, most of the food sources come from animals and plants. There are cases where this does not apply such as food sources from fungi such as mushrooms and even bacteria used in food that involves fermentation such as yogurt and pickles.
Cereals are concrete examples of food coming from plants. Wheat and rice are food coming from plants which are important staple food for many countries in the world. Fruits and vegetables are nutritious food coming from plants. Legumes are also plant products that are consumed as food by many people also.
Dairy products are food coming from animals. Milk, cheese and meat are rich sources of protein coming from animals. Even seafood is food coming from animals in the sea such as fish, clams, crabs and other crustaceans. Poultry products are also very common such as chicken meat and fresh eggs.
Food sources and other related information about food can be found in the following links: