After overtaking, the truck behind you flashes briefly once: this is what the driver wants to tell you.

the truck is therefore always wise.

Not every flash of light means the same thing.

If you see a truck flashing behind you, pay close attention to the moment it happens. Does the flash occur exactly after you have 

In the Netherlands, according to traffic regulations, flashing and audible signals primarily serve a function in the event of imminent danger. Therefore, legally, a brief flash

of light does not mean you are granted permission to change lanes. Nor does it give you the right of way. At most, the driver behind you can indicate that he sees sufficient space.

That