Food processing is the transformation of agricultural products into food, or of one form of food into other forms. Food processing takes many forms, from grinding grain into raw flour, home cooking, and complex industrial methods used in the making of convenience foods. Some food processing methods play important roles in reducing food waste and improving food preservation, thus reducing the total environmental impact of agriculture and improving food security.

Convenience food is food that is commercially prepared for ease of consumption, and is usually ready to eat without further preparation. It may also be easily portable, have a long shelf life, or offer a combination of such convenient traits. Convenience foods include ready-to-eat dry products, frozen food such as TV dinners, shelf-stable food, prepared mixes such as cake mix, and snack food. Food scientists now consider most of these products to be ultra-processed foods and link them to poor health outcomes.