Everytime you move a train you will receive a share in that particular Railway. There are 7 Railroads in all, and each has 14 shares. The biggest shareholder will receive a payout equal the number of towns and cities on the closing line, and the second biggest shareholder will receive a payout of half that amount. Thus a railway will probably not be in operation for long and it is not uncommon for a game to end with only one single line intact. Each player has 7 wooden Station-buildings in his color.
Goods begins the game in groups of three in the Trading-cities.
Passenger tokens yields a similar bonus. All in all a game with so many things going on that you need to play a trial game before you understand the mechanics, but everything is really very straightforward and in your second game everything but the strategy will seem simple enough to you.