When cruising through neighbourhoods with no stop signs cars to the right always have the right of way, and the speed limit within the city is 50kph unless otherwise noted. The fastest you can go on the highways within the city is 100kph, and the unlimited speed limits don’t kick in on the Autobahn until you’re well outside the city. If you get caught speeding by a traffic camera you’ll get a ticket in the mail, and rental car companies will forward these tickets to your home address, so you won’t escape them. The police also set up speed traps and may require you to pay on the spot.
A diamond-shaped sign with a yellow centre means you have the right of way at an intersection, and all traffic lights also have such signs to show who has the advantage should the lights go out, which seems to happen with odd frequency for a society that prides itself on order. You may only pass on the left and Germans do, in fact, only pass on the left.