How does backburning work when trying to contain out of control wildfires?

You need 3 things to sustain a fire - heat, oxygen, and fuel. Remove one of them and the fire goes out. Backfiring is a way of removing fuel from the fire's path.How does backburning work when trying to contain out of control wildfires?
The goal is to set a fire that burns back toward the oncoming fireline and consumes the fuel in between, stopping the wildfire's progress.





It's tricky and frequently goes wrong, making thing worse. But when it works it can definitely stop a wildfire.