The petroleum industry, also known as the oil industry or the oil patch, includes the global processes of exploration, extraction, refining, transportation (often by oil tankers and pipelines), and marketing of petroleum products.
The oil and gas industry is usually divided into three major sectors: upstream (or exploration and production - E&P), midstream and downstream.   The upstream sector includes searching for potential underground or underwater crude oil and natural gas fields, drilling exploratory wells, and subsequently operating the wells that ...
Petroleum engineering is a field of engineering concerned with the activities related to the production of Hydrocarbons, which can be either crude oil or natural gas. Exploration and production are deemed to fall within the upstream sector of the oil and gas industry.
The S&P Global list is restricted to publicly traded companies, and only integrated oil and gas, oil and gas exploration and production, oil and gas refining and marketing, and oil and gas storage and transportation companies were included on the list below.
According to the American Petroleum Institute, the oil and natural gas industry supports nine million U.S. jobs and makes up seven percent of the nation's gross domestic product. As of 2021, the petroleum and natural gas industries support 10.3 million jobs and make up 8% of the U.S. GDP.
India also produces petroleum products and produced 233.51 Mt in 2020–21, a decline of 11.19% over the previous year. Among petroleum products, high speed diesel oil accounted for 43%, followed by motor gasoline (15%). Production of petroleum products grew by a CAGR of 1.56% over the previous decade.