Propane, three alkanes. Usually gaseous, but generally compressed into liquid after transport. When crude oil or natural gas is processed, propane can be obtained from the finished product. Propane is used as fuel for engines, barbecue food and home heating systems.

Propane is used as a fuel for barbecues, portable stoves and motor vehicles. Propane is often used to drive trains, buses, forklifts and taxis, and is used to serve as a recreational vehicle and fuel for heating and cooking during camping. In some rural areas in North America, propane is used to fill stoves, water heaters, and dry-cell phones for heat-producing appliances. As of 2000, 6.9 million American households used propane as their main fuel. Commercial "propane" fuel, or liquefied petroleum gas, is impure. In the United States and Canada, the main ingredient is 90% of propane plus up to 5% of butane and propylene and odor agents. This is the domestic standard of the United States and Canada, usually writing HD-5 standards. It is to be noted that liquefied petroleum gas (LPG) prepared from methane does not contain propylene and only propane obtained from crude oil refining process. Similarly, in some other countries, such as Mexico, the standard content of butane is relatively higher.