Tram systems are common throughout Europe and were common throughout the Western world in the early 20th century. In Canada most cities once had a streetcar system, but today Toronto's TTC is the only operator of streetcars. In Australia trams are in use in several cities, most extensively in Melbourne with its W-class tram.
The name "tram" is from Low German traam, meaning the "beam (of a wheelbarrow)".
Early trams were pulled along by horses. Later trams, known as cable cars, attached to a moving cable underneath the road. The cable would be pulled by a steam engine at a powerhouse. Railed vehicles pulled by cable up the hills at steep incline, such as Hong Kong's Victoria Peak Tram, and Monongahela and Duquesne Inclines in Pittsburgh, Pennsylvania, USA, are also called trams, but are more accurately funiculars. Modern trams generally use overhead electric cables, from which they draw current through a pantograph or a trolley pole.
There are also double-decker trams, see Hong Kong Tramways.
Double track tram lines are sometimes at narrow passages single track, or, to avoid switches, have the tracks intertwined, e.g. in the Leidsestraat in Amsterdam on three short stretches (see map detail).
The electric tram was invented by Werner von Siemens.
In some countries, the word "tram" also refers to small localized transportation systems that do not run on rails. These can be small linked vehicles used to shuttle visitors around a tourist attraction or from a large parking lot into a building such as a shopping center. These trams run on regular paved road with rubber tires. Suspended cable cars, such as those found in ski resorts, may also be called trams, see Aerial tramway.
In the United States of America, most trams were removed by the 1950s. Among the reasons, the US firm of General Motors formed a separate subsidiary named "National City Lines", whose business mission was to buy out tram/streetcar operations all around the US and replace the trams with fleets of buses. Not all trams were removed; the San Francisco cable cars are the most famous example of trams in the United States. More recently some American cities have built light-rail systems which operate partially in the right-of-way of city streets. These systems could be called trams by Europeans and Australians but are generally not known by that name within the US.History
Trams in the USA