examples of freight cars 
The shape of the cars varies depending on the type of cargo being transported.
Car that is usually at the end of the train; it houses personnel, provisions and tools.
Closed-box insulated car with a refrigeration unit for carrying perishable foodstuffs.
Car for carrying bulk cargo; it has dump doors on the bottom for unloading the cargo.
Flat car for carrying semitrailers.
Car with slatted sides for carrying livestock; it sometimes has two decks.
Car with a sealed reservoir for carrying liquids and gases.
Car covered with a waterproof casing and having sliding side doors, for transporting cargo that must be protected from the weather and theft.