Farmscape. A farm is an area of land that is devoted primarily agricultural processes with the primary objective of producing food and other crops; it is the basic facility in food production. The name is used for specialised units such as arable farms, vegetable farms, fruit farms, dairy, pig and poultry farms, and land used for the production of natural fibres, biofuel and other commodities. It includes ranches, feedlots, orchards, plantations and estates, smallholdings and hobby farms, and includes the farmhouse and agricultural buildings as well as the land. In modern times the term has been extended so as to include such industrial operations as wind farms and fish farms, both of which can operate on land or sea. Farming originated independently in different parts of the world, as hunter gatherer societies transitioned to food production rather than, food capture. It may have started about 12,000 years ago with the domestication of livestock in the Fertile Crescent in western Asia, soon to be followed by the cultivation of crops. Modern units tend to specialise in the crops or livestock best suited to the region, with their finished products being sold for the retail market or for further processing, with farm products being traded around the world. Modern farms in developed countries are highly mechanized. In the United States, livestock may be raised on rangeland and finished in feedlots and the mechanization of crop production has brought about a great decrease in the number of agricultural workers needed. In Europe, traditional family farms are giving way to larger production units. In Australia, some farms are very large because the land is unable to support a high stocking density of livestock because of climatic conditions. In less developed countries, small farms are the norm, and the majority of rural residents are subsistence farmers, feeding their families and selling any surplus products in the local market. The word in the sense of an agricultural land-holding derives from the verb to farm a revenue source, whether taxes, customs, rents of a group of manors or simply to hold an individual manor by the feudal land tenure of fee farm. The word is from the medieval Latin noun firma, also the source of the French word ferme, meaning a fixed agreement, contract, from the classical Latin adjective firmus meaning strong, stout, firm. As in the medieval age virtually all manors were engaged in the business of agriculture, which was their principal revenue source, so to hold a manor by the tenure of fee farm became synonymous with the practice of agriculture itself. Farming has been innovated at multiple different points and places in human history. The transition from hunter-gatherer to settled, agricultural societies is called the Neolithic Revolution and first began around 12,000 years ago, near the beginning of the geological epoch of the Holocene around 12,000 years ago. It was the world's first historically verifiable revolution in agriculture. Subsequent step-changes in human farming practices were provoked by the British Agricultural Revolution in the 18th century, and the Green Revolution of the second half of the 20th century. Farming spread from the Middle East to Europe and by 4,000 BC people that lived in the central part of Europe were using oxen to pull plows and wagons. A farm may be owned and operated by a single individual, family, community, corporation or a company, may produce one or many types of produce, and can be a holding of any size from a fraction of a hectare to several thousand hectares. A farm may operate under a monoculture system or with a variety of cereal or arable crops, which may be separate from or combined with raising livestock. Specialist farms are often denoted as such, thus a dairy farm, fish farm, poultry farm or mink farm. Some farms may not use the word at all, hence vineyard, orchard, market garden or truck farm. Some farms may be denoted by their topographical location, such as a hill farm, while large estates growing cash crops such as cotton or coffee may be called plantations. Many other terms are used to describe farms to denote their methods of production, as in collective, corporate, intensive, organic or vertical. Other farms may primarily exist for research or education, such as an ant farm, and since farming is synonymous with mass production, the word farm may be used to describe wind power generation or puppy farm.