PassRight-Of-Way
Where: On a through route, where it meets a series of side roads that must give way to it.
Purpose: To inform you that the road you are travelling on has right of way over the roads joining it. The bold line is your road; the faint line is the side road.
Action Required by Driver: Carry on, but do not confuse information with safety. Right of way is something other drivers are obliged to give you — it is not a guarantee that they will. Keep scanning the side roads, and cover the brake where visibility into them is poor.
Information, not regulation
This is a blue information sign, not a regulatory one. It tells you how the junctions ahead are arranged. The actual control at each junction — a stop sign, a yield sign or a signal — is what binds the other driver.