A hopper car is a type of railway freight car that is designed to transport bulk goods, such as coal, grain or cement. However, there are different names and synonyms for this type of car depending on the region and the type of cargo it transports. For example, in North America, it is often called a coal car, grain car or mineral car. In Europe, it is sometimes referred to as a wagon or a goods wagon. Other regional variations include gondola cars, which are used for transporting loose materials such as gravel, and boxcars, which have doors on the sides and are used for carrying packaged goods.