The process of extracting oil from deep underground rock formations is oil drilling.

Oil drilling is the primary method used to extract oil from deep underground rock formations. The process involves drilling a well into the Earth's surface to reach oil deposits trapped in rock layers. Once the well reaches the oil reservoir, it can be brought to the surface using natural pressure or mechanical pumps. This method is widely used to access conventional oil reserves, differing from hydraulic fracturing, which is applied to extract oil and gas from shale formations. Oil drilling is critical for tapping into the Earth's deeper, more traditional oil reserves and contributing to global energy production.