Chances are that most Americans think railroads are a thing of the past, a nostalgic technology that once dominated the American scene before being upstaged by automobiles, trucks, and airplanes.  One major reason for this belief is that the railroad has simply passed out of their experience.  Relatively few people take trains, and the only other point of contact for most people is a track crossing where they might sit for some time waiting for a seemingly endless freight to go by.  In fact, the sheer length of such trains provides a clue that the railroads are still very much with us.  Far from being a moribund antique of an industry, it has evolved into a dynamic, prosperous one.