Nash equilibrium

I came across the concept of Nash equilibrium for games. As far as now I associated the name Nash to the movie "A beautiful mind", which I liked very much.
My professor of game theory at the university was so weird that I never really understood what he said. He looked like Bakunin and always had a stinky pipe in his hands.
But going back to the equilibrium, a game is said to be in such state when even if a player knew the strategies of all other players, he would not find any benefit in changing his strategy.
Described like this it sounds strange, but imagine I have two roads to drive to reach my office. If I know that everybody who wants to go there is taking one path and the other is empty (no traffic), I will choose the path without traffic. This game is not in Nash equilibrium, because I benefit by knowing other players' strategies. But if I know that the other drivers will equally distribute on both paths, than it does not really matter if I choose one or the other. This is an example of game in Nash equilibrium.