Oil is a fossil fuel composed of dead plants and animals that are buried underground for many years and exposed to extreme heat and pressure. It is one of the world's most valuable natural resource and is measured in USD. The fluctuation of crude oil prices affects the global economy, and also affects our daily lives as prices of commodities are dependent on oil prices. Oil traders select the most widely used types of oil to determine the price per barrel. This benchmark is considered a reference price for buyers and sellers of crude oil. The US oil uses an industry benchmark called the West Texas Intermediate (WTI) which is a blend of several U.S. domestic streams of light sweet crude oils that are easy to break down in the refining process. The supply and demand of oil in the world market, its quality, ease of refining and investment in oil futures are factors that determine the US oil prices. All in all, the oil market is quite complex, and it is important for investors to keep track of the current prices and understand which factors affect the oil prices.