Factory farming is the dominant method of 'food' animal production used by agribusiness in developed nations around the globe. Factory farms are an outgrowth of the development of assembly lines in commercial industry and the development of antibiotics in the pharmaceutical industry. Before the development of factory farms, most animals raised for food were free to roam outdoors on small farms. The lives of the animals were relatively peaceful, until they were slaughtered and their body parts sold at local markets. The environmental impact of small farming was minimal. Today, agribusiness giants, using vast amounts of antibiotics, growth hormones, energy, plant food, and water raise animals indoors, monitoring their every move so as to produce the most meat for the lowest price. But there are hidden (and not so hidden) costs, to the environment, to the animals, and to public health.