What can I say... I really love realistic simulators! And this one is good. The controls, weather, graphics, etc is so real. Basically, you run your own trucking business, have to take on delivery jobs, navigate with a GPS, drive through interesting countryside, and deal with all the normal issues along the way liking putting in gas, not exceeding the speed limit, being cautious in wet weather, getting lost, etc.
This is the Beta version running on Steam for Linux, but it also runs on Windows and Mac. I actually bought the "Windows version" but great thing with Steam is, it then also runs on the other platforms if the version is available.