I bring this up because Drivers' Ed never mentioned it.
For an obvious example, using turn signals is being predictable. Not passing on the right is being predictable. Driving at the same speed as the rest of the traffic is being predictable. There are all kinds of traffic laws, but most boil down to just be predictable.
For the cyclists, please don't draft behind some unwitting driver. (Yes, I see this now and then.) Please don't randomly weave in and out of traffic. And please don't bike across the crosswalk, walk your bike across it. Drivers cannot react fast enough to a bike darting across the road.
And when the bike lane does a Kriss-Kross across a car lane, stay alive and don't do it in front of traffic.