Meat is animal flesh that is eaten as food. Humans have hunted and killed animals for meat since prehistoric times. The advent of civilization allowed the domestication of animals such as chickens, sheep, rabbits, pigs and cattle. This eventually led to their use in meat production on an industrial scale with the aid of slaughterhouses.
Meat is mainly composed of water, protein, and fat. It is edible raw, but is normally eaten after it has been cooked and seasoned or processed in a variety of ways. Unprocessed meat will spoil or rot within hours or days as a result of infection with and decomposition by bacteria and fungi.
Meat is important to economies and cultures, but the production and consumption of meat pose risks for human health, animal health, and the environment. Many religions have rules concerning the eating and not eating of meat. Vegetarians and vegans may not eat meat because of concerns about the ethics of eating meat, environmental effects of meat production or health effects of consumption.