An oil field is an area where oil wells extract crude oil from beneath the ground. Oil fields are large geographical areas in many cases and in some regions the crude oil is far beneath the ground. Therefore, to fully extract all the crude oil present, a great deal of labor and many types of oil field equipment are needed. There is a large variety of oil field equipment needed in order to extract crude oil with oil wells. The wells, with the multitude of parts, need to be erected. Exploratory wells may be needed to probe the edges in order to find oil. Pipelines need to be added to transport the oil out of the oil fields. Support facilities are needed as well, and of course tools and equipment are needed for all the individuals working at the oil wells. In addition, all oil fields require oil field equipment transportation to move the equipment from one site to another.

Many oil fields also need additional equipment because they are located far from towns and cities and in some cases are located in harsh environments. Equipment for oil fields may include housing for the workers, which often needs to be built from the ground up if the oil field is far from civilization. Since workers are often needed at an oil field for months or years, electrical and power systems may need to be built or complex generator systems may need to be introduced in order to keep machines and homes running. If the oil fields are located in cold climates, heating equipment may be needed to protect pipelines and essential structures. Many companies have emerged to supply the oil industry with oil field equipment: Schlumberger Limited, Baker Hughes, BJ Services, Bechtel, Esso, and Halliburton are just a few of the better-known names.

Essentially, an oil field is partly a small city and partly a large-scale industrial operation. As such, it requires all the equipment you may expect to see in both. The exact oil field equipment needed at each site varies, depending on the size of the oil field and the specific climate, but in general oil field equipment includes:

• Transportation. This can include trucks and cars. For offshore drilling, it may include helicopters and marine vessels.
• Cranes. Large cranes are used to build structures on oil fields and to transport piping and install heavy equipment.
• Drilling rigs
• Pump jacks. These drills have a nodding arm and are often called "nodding donkeys" as a result.
• Gas engines.
• Production tubing.
• Tanks.
• Construction equipment. This is often used to build homes and support structures on site.
• Gas separators.
• Heat tape.
• Generators.
• Explosives or other clearing equipment. In many oil fields, considerable amounts of earth, trees, and other natural phenomena must be moved to access the oil.
• Pipe fittings.
• Safety supplies. These can include hard hats, construction boots, goggles, protective face shields, ear plugs and other supplies.
• Mooring systems and offshore plantforms. If the oil is drilled offshore, a mooring system needs to be provided to provide a stable place for equipment and staff to stand. Mooring systems themselves require a large range of oil field equipment, including marine risers, analyzed drill bits, pipe line components, down-hole drilling components, and other equipment.
• Piping. Piping is required to transport crude oil and to remove excess natural gas for burning.
• Pressure vessels. Pressure vessels are needed when drilling is done off-shore.