Butane is a highly volatile, colorless hydrocarbon gas with an odor similar to petroleum. Like propane, pentane, hexane, and other hydrocarbons, it is used to extract cannabinoids, terpenes, and other compounds from the cannabis plant to make concentrates, collectively called BHO, or butane hash oil, which can vary in consistencies and textures. Butane is one of the most ubiquitous hydrocarbons in the world. It is highly flammable and needs to be handled by licensed, trained professionals.