drivers use various informal signals on the road. They can send each other short messagesusing their headlights and turn signals. A single short flash of light after an overtaking maneuver often has a very practical meaning. Below, you can read exactly what that signal entails and why truck drivers do this.trucks often drive at approximately the same speed. As a result, the speed difference during an overtaking maneuver is sometimes only a few kilometers per hour. Consequently, a truck can drive alongside another truck for quite a long time.
After overtaking, the truck behind you flashes briefly once: this is what the driver wants to tell you.
