Agriculture involves the process of producing food, feed, fiber and many other desired products by the cultivation of certain plants and the raising of domesticated animals or livestock.
Agriculture is also known as “farming”, while scientists, inventors and others devoted to improving farming methods and implements are also said to be engaged in agriculture.
Subsistence agriculture involves farming on a small scale with limited resource inputs, and produces only enough food to meet the needs of one’s family.
At the other end is commercial intensive agriculture, including industrial agriculture. Such farming involves large fields and/or numbers of animals, large resource inputs (pesticides, fertilizers, etc.), and a high level of mechanization. These operations generally attempt to maximize financial income from grain, produce, or livestock.
Modern agriculture extends well beyond the traditional production of food for humans and animal feeds.
Other agricultural production goods include timber, fertilizers, animal hides, leather, industrial chemicals (starch, sugar, alcohols and resins), fibers (cotton, wool, hemp, silk and flax), fuels (methane from biomass, ethanol, biodiesel), cut flowers, ornamental and nursery plants, tropical fish and birds for the pet trade, and both legal and illegal drugs (biopharmaceuticals, tobacco, marijuana, opium, cocaine).
The 20th Century saw massive changes in agricultural practice, particularly in agricultural chemistry. Agricultural chemistry includes the application of chemical fertilizer, chemical insecticides, and chemical fungicides, soil makeup, analysis of agricultural products, and nutritional needs of farm animals.
Beginning in the Western world, the green revolution spread many of these changes to farms throughout the world, with varying success.
Other recent changes in agriculture include hydroponics, plant breeding, hybridization, gene manipulation, better management of soil nutrients, and improved weed control.
Genetic engineering has yielded crops which have capabilities beyond those of naturally occurring plants, such as higher yields and disease resistance