The term "oil companies" refers to businesses that engage in the exploration, extraction, refining and distribution of petroleum products. These companies are involved in every aspect of the oil industry from searching for new sources of crude oil and natural gas, drilling wells, transporting the fuel through pipelines or tanker ships, processing it into various grades of motor fuels, heating oils, lubricants, asphalt and other petroleum-based products. Some of the largest oil companies in the world include ExxonMobil, Royal Dutch Shell, BP, Chevron, ConocoPhillips, Total S.A., and Eni. These companies have a significant impact on global energy markets, as well as on the economy, environment, and geopolitics of many countries around the world.