Light crude oil is liquid petroleum that has a low density and flows freely at room temperature.
The clear cut definition of light and heavy crude varies because the classification is based more on practical grounds than theoretical.
Canada also uses the SI of units to measure oil rather than American oil industry conventional units, and the base temperature for density calculations is different in Canada at 15 °C (59 °F) than the US at 60 °F (15.56 °C), resulting in slightly different density values.
[7] From below $20 a barrel in early 2002, it rose to an intraday peak of $70.85 at the end of August 2005 in the aftermath of Hurricane Katrina.
But, by August 2007, the price had reached a record high of $78.71, amid production output concerns in the North Sea and Nigeria.