In oil exploitation, the earliest tool used to hold oil was indeed a barrel. But at that time, the bucket was just a load-bearing tool, not used to calculate the volume and so on. With the passage of time, many people have developed the habit of using barrel oil. Gradually, people get used to using barrels as the unit of measurement of oil.

At present, barrels are the most important unit of crude oil futures pricing, and the futures trading volume of several major crude oils accounts for almost all the market share. But some crude oil futures are not priced in barrels, just like the crude oil futures of Tokyo Stock Exchange in Japan are priced in kilograms.

Many people may have the misunderstanding that crude oil is traded in barrels, because the price is calculated in barrels, which has also caused most people's misunderstanding. In fact, crude oil is mainly transported by pipeline, from oil fields to refineries or to export ports.

As follows:

Directly transported to storage through local pipelines, barrels are basically just a unit of valuation, but actually it is not how much a barrel costs.

Using "barrels" to measure the global coverage of crude oil is just like the status of the dollar. Crude oil can be said to be one of the few commodities with unified international pricing, and it is denominated in US dollars. Because most of the standards of the oil industry now come from the United States, and the United States is a big oil consumer, it still has a certain right to speak in this regard.

It is undeniable that the US dollar, as a global reserve currency, is more stable than other currencies. So it is understandable that crude oil will be priced in dollars.

The most commonly used unit of measurement for oil is the capacity unit, which is 42 gallons. Because the density of oil produced in different places is different, the weight of a barrel of oil is different. It depends on the level of refining. Good places can reach more than 50%. Most of the rest is extracted for other purposes.