Number 2 (No.2) fuel oil is used for home heating, while diesel fuel is used to power vehicles with diesel engines such as railroad locomotives, trucks, city buses and some cars.
Diesel fuel is easily purchased at many gas stations throughout the world. Three different types of diesel fuel exist and are classified by the temperature used in the distillation process. The primary advantage of diesel fuel over gasoline is the lower flashpoint (temperature at which the fluid will ignite).
No. 2 fuel oil is used for domestic and commercial heating and is essentially the same as diesel fuel, however has a higher sulfur level. No. 2 fuel oil is also used with stoves and portable heaters.
Diesel fuel and No. 2 fuel oil are produced by the same process. A 42-gallon drum of crude oil produces 12 gallons of distillate, 10 gallons of which becomes diesel and two of which becoming No. 2 fuel oil.
