Urban hybrid systems
Introduction
Urban rail transportation is an umbrella term that encompasses various types of local rail systems that serve passengers in and around urban or suburban areas. The set of urban railway systems can be broadly subdivided into the following categories, which sometimes overlap because some systems or lines have multiple types of aspects.
Types of urban rail transport
Tram
A tram is a railway-based transportation system that runs primarily or entirely along streets, with relatively low capacity and frequent stops; However, modern trams have a higher passenger capacity than traditional trams. Passengers typically board at street or curb level, although low-floor trams may allow boarding at street level. The longest distance lines are called interurban or radial lines. Modern trams also operate as multiple-coupled self-propelled trains rather than individual trams and are often included within the broader term light rail,[1][2] however, they differ from these in that trams frequently share the platform with vehicular traffic and do not have traffic light priority.[3].
The term tram is used in most of the world. In North America, these systems are called "streetcar" or "trolley"; In Germany, these systems are called "Straßenbahn" which literally translates to "street train" or "street railway".
Light Rail
A light rail is a rail-based transportation system that has greater capacity and speed than a tram, typically operating with an exclusive right-of-way separate from automobile traffic, but not totally separated from other traffic like a subway is. Light rail also typically runs on multiple unit trains rather than individual trams. It emerged as an evolution of trams. Light rail systems vary considerably in speed and capacity. They range from slightly improved tram systems to systems that are essentially rapid transit but with some level crossings.
The term "light railway" is the most commonly used, although German systems are called "Stadtbahn" (which translates as "urban railway").