Every drilling company makes money by constructing an oil well to bore through the earth's surface. The company can thereby find and obtain valuable petroleum oil. During the process, some natural gas is usually also obtained.
The oil drilling industry is incredibly lucrative, and company executives are able to make astonishing profits each year.
Some oil drilling companies are located offshore. These companies construct large platform rigs over the water they hope to find oil in. The construction process on these barges is lengthy, and requires a great deal of precision equipment. Once the offshore rigs have been completed, the company then begins to pump the petroleum oil up from the fluid column to the platform. It can then be sent to a refinery.
Other oil drilling companies are located on land. In the United States, most unused oil reservoirs are located in Alaska, and so a large amount of drilling takes place there. Oil companies take the time to explore each potential drilling site or field. Then, if they decide that they'll be able to obtain significant quantities of oil or gas from the site, they begin to lay down a network of pipes. These pipes, which the companies construct with highly specialized tools and machines, can transport oil great distances.
Drilling is a complicated process, and a variety of methods are often used to extract the oil. Horizontal, or directional wells, can be used, for instance, on land in lieu of more traditional wells. Rotary drilling is also often used to maximize profits.