Crude oil is a naturally occurring hydrocarbon found in rock formations underground. It is a dark, sticky liquid composed mainly of carbon and hydrogen. Crude oil is the world's most actively traded commodity and is refined into fuels like gasoline and diesel. The first commercial oil wells were drilled in the 1850s in Romania and India, and global crude oil consumption has exceeded 875 billion barrels to date. Crude oil futures are traded on exchanges like NYMEX and MCX, with key factors influencing prices including supply, demand, geopolitics, and weather conditions.