Cubic Meter (m³)
The cubic meter (m³) is the official SI unit for volume, representing the space within a cube whose sides are each one meter in length. Established as part of the metric system in the late 1700s, it acts as a foundation for quantifying large volumes. A single cubic meter equals 1,000 liters and is routinely used across engineering, construction, shipping, and the environmental sector for consistent volume calculations. Its use promotes accuracy and standardization in global commerce, scientific research, and industrial processes.
Barrel (oil, bbl)
The oil barrel, symbol bbl, is a unit of volume commonly used in the petroleum industry. Its origins date back to the mid-19th century, when the American oil industry adopted the wooden barrel as a standard for storage and transportation. In 1866, the barrel was officially set at 42 US gallons (about 159 liters) to unify trade and pricing. Although physical barrels are no longer used, the “barrel” remains a widely recognized standard for oil production, consumption, and trading. The oil barrel is commonly referenced in discussions of energy, economics, and industrial development as a non-metric unit of volume.