If you are driving down a freeway with 2 lanes going in the same direction you will notice the left lane is usually the fastest lane. If you are in the left lane flowing with the left traffic you are fine. BUT and this is a big BUT. If you are in the left lane and nobody is in front of you and you also have a vehicle or a string of vehicles behind you that means you should not be in that lane because you are going too damn slow and should move to the right lane as soon as possible to let the faster traffic go by. This does not matter if you are already going the maximum freeway speed. This does not apply to the HOV lane.
The first sign you are in the wrong lane at the wrong time is when the cars behind you have to go into the right lane or HOV lane to pass you then they cut back in front of you to keep going. You will likely notice those drivers giving you a glare. If you’re lucky that is all you will get otherwise it will soon be more likely you will get a $109.00 fine each time.