The outback is the remote and interior and north of Australia, although the term colloquially can cover any lands outside of the main urban areas. The term outback is generally used to refer to locations that are comparatively more remote than those areas deemed "the bush". The outback does not officially exist within any governmental frameworks or boundaries. Many local government shires do use the term to enhance tourist appeal for their own shire (see picture at right.)
The marginally fertile parts, mainly within the Lake Eyre Basin, are known as rangelands and have been traditionally used for sheep or cattle farming, on sheep stations and cattle stations which are leased from the Federal Government. Whereas these grassy areas have fairly fertile clay soils, the remainder of the outback has exceedingly infertile paleosols which cannot support fodder nutritious enough for the economic raising of stock. Although the north of Australia has high (if extremely seasonal) and fairly reliable rainfall, giving it almost all the continent's runoff, the soils there are so poor and eroded (consisting mainly of ironstone or bauxite) as to make cropping impossible even with fertilisers such as superphosphate.
Along with agriculture, tourism and mining are the main economic activities in this vast and sparsely settled area. Due to the complete absence of mountain building and glaciation since the Permian (in many areas since the Cambrian), the outback is extremely rich in iron, aluminium, manganese and uranium ores, and also contains major deposits of gold, nickel, lead and zinc ores. Because of its size, the value of grazing and mining is considerable.
Organised travel to the outback is popular, although some Australian and international tourists travel in their own vehicles. Such a trip, particularly once off the few bitumen roads in the outback, requires considerable advance planning and a suitable vehicle (usually a four wheel drive). On remote routes considerable supplies and equipment may be required, this can include prearranged caches. Some trips cannot be undertaken safely with a single vehicle instead requiring a convoy approach. Deaths from tourists and locals becoming stranded on outback trips occur, and rescues for the ill-prepared are a regular occurrence.