Highway hypnosis is a term used to describe a trance-like feeling that can happen when you are driving on the highway in your car for a long time. When this happens, you can feel like you're in a kind of a dream world, and it can feel like you are going on auto-pilot and just kind of "zoning out" of your surroundings. It can be dangerous because it means you're not paying close enough attention to the road and all the other cars around you. So if you start to feel highway hypnosis, it's important to take a break from driving and pull off the road or switch drivers.