Oil which are deposited million years ago which are extracted by the traditional drilling methods, they are under certain atmospheric pressure thus they liquid flow without any additional stimulation for oil extraction. The unconventional oil which requires advanced production method for extracting the crude oil due to its heavy formation thus it can flow freely hence the unconventional oil is extracted by the vertical drilling techniques. It is more expensive than conventional oil. Unconventional Oil is rising in demand for fossil fuels and falling reserves of conventional It is a revolutionary technology in which hard to access Oil reserves economically.