In general terms, eating (formally, ingestion) is the process of consuming something edible, i.e. food, for the purpose of providing for the nutritional needs of an animal, particularly their energy requirements. All animals must eat other organisms in order to survive: carnivores eat other animals, herbivores eat plants, and omnivores consume a mixture of both.
While the process of eating varies from species to species, in humans eating is performed by placing food in the mouth and then swallowing it, with chewing often occurring between these actions. Eaten food is then digested.
Most homes have a kitchen or kitchenette devoted to preparation of meals and food, and many also have a dining room or another designated area for eating. Dishware, silverware, drinkware for eating and cookware and other implements for cooking come in an almost infinite array of forms and sizes. Most societies also have restaurants and food vendors, so that people may eat when away from home, lack the time to prepare food, or wish to use eating as a social occasion. Occasionally, such as at potlucks and food festivals, eating is in fact the primary purpose of the social gathering.
Most individuals have fairly regular daily patterns of eating, and commonly most eating occurs during two to three meals per day, with snacks consisting of smaller amounts of food being consumed in between. The issue of healthy eating has long been an important concern to individuals and cultures. Among other practices, fasting, dieting, and vegetarianism are all techniques employed by individuals and encouraged by societies to increase longevity and health. Leading nutritionists believe that instead of indulging oneself in 3 large meals each day, it is much healthier and easier on the metabolism to eat 5 smaller meals each day (e.g. better digestion, easier on the lower intestine to deposite wastes; whereas larger meals are tougher on the digestive track and may call for the use of laxatives). Eating can also be a way of making money.
Physiologically, eating is generally triggered by hunger, but there are numerous physical and psychological conditions that can affect appetite and disrupt normal eating patterns. These include depression, food allergies, bulimia, anorexia nervosa, pituitary gland misfunction and other endocrine problems, and numerous other illnesses and eating disorders.
A chronic lack of nutritious food can cause various illnesses, and will eventually lead to starvation. When this happens in a locality on a massive scale it is considered a famine.
If eating and drinking is not possible, as is often the case when recovering from surgery, alternatives are enteral nutrition and parenteral nutrition.