Barrels which are used for oil storage and transport are called as Oil Barrels. They are generally used for storing crude oil and other petroleum products. These oil barrels are used to measure oil in the United States. The standard oil barrel has a capacity to hold 42 U.S. gallons of crude oil. Even for global reporting the American Oil Exchanges report their production volumes in barrels.

During 19th century, the oil barrels are made up of wood unlike the modern day 55 gallon steel drums. They were used for shipping purposes. The use of these barrels originated in Pennsylvania oil fields. In those days, there was no particular unit of measurement. Then the people of those days decided to have a standard unit of measurement to convince their buyers. Then the origin of 42 gallon oil barrel took place. Even though the introduction of oil tankers has overtaken the usage of these barrels, even today these barrels are considered as the standard measurement in many places of America.

BPD, which means Barrels per Day is a measurement used to describe the rate of the crude oil consumption per day. And another one is BCD, which means Barrel per calender day is a standard petroleum downstream industry measurement of refinery. In olden days, oil barrels were made with wood, but now a days they are made with different materials like iron, steel and cement. These barrels are also available in different sizes, shapes and colors.

Oil barrels are not of much use for common people but still they are of big help for commercial purposes.