The oil and gas industry is usually divided into three major components: upstream, midstream and downstream. The midstream sector involves the transportation, storage, and wholesale marketing of crude or refined petroleum products. Pipelines and other transport systems can be used to move crude oil from production sites to refineries and deliver the various refined products to downstream distributors. Natural gas pipeline networks aggregate gas from natural gas purification plants and deliver it to downstream customers, such as local utilities.

Wikipedia. CC BY-SA 4.0. Updated Mar 31, 2026.