The North West, North West Coast, North Western Australia and North West Australia, are usually informal names for the northern regions of the State of Western Australia. However, some conceptions of "North West Australia" have included adjoining parts of the Northern Territory (NT) – or even the entire NT (see below). Major offshore islands include Barrow Island, Monte Bello Islands and the Dampier Archipelago. Apart from land areas, the term "North West" is also used for seabed oil and gas fields of the North West Shelf.