Of course the transportation of passengers was one of the important functions of the steamboats. But they were also used as the only chance to transport big loads of cotton and other agricultural products.
Passengers, who just wanted to get from one place to another as cheap as possible spent their time aboard somewhere between the cotton and the other load at the main deck. More comfortable but often very expensive travelling was offered at the cabin decks. Only the rich people could afford to have a cabin and to have dinner at the great salons.
Approximately from 1950 on, the transport of passengers got more and more important. Therefore to most of the ships one ore more additional cabin decks were added. The one above the main deck was called “texas deck”. The one above the texas was usually called “sun deck”. With one or two additional decks the boats became luxurios excursion boats, the transportation of cotton and other goods more and more were taken over by the new railroad.
Bars and theatres were added to the steamboats, expensive wood, glas works and metals made the boats to something like swimming palaces. Excursions, most of them for fun not for transportation, became very expensive, but also a great, nostalgic experience.