What is the difference between a normal tornado and a fire tornado?

A normal tornado is a violently rotating column of air the descends from the rotating updraft of a thunderstorm. A fire tornado or firewhirl, which is technically not a tornado, is a vortex of smoke and/or flame that forms at ground level from the updraft of an intense fire. Firewhirls can potentially produce winds equivalent to an EF0 or EF1 tornado, but the main threat is their ability to spread a fire further.