Light rail is a form of transit which is most often used in urban areas as part of a mass transit system. Like other types of transit with “rail” in their titles, light rail consists of trains which run along tracks. The trains used in a Light Rail Transit (LRT) system are most often electric, although some LRT systems use diesel as well. As a general rule, this form of rail transport is designed for humans, rather than manufacturing goods.
Several things set light rail aside from other types of rail transit, such as subways, heavy rail, and rapid transit systems, all of which use trains. The most important difference is that light rail usually shares the public right of way. For example, the tracks for many light rail trains are run in public streets sharing space with traffic. In other cases, a light rail train runs on a dedicated area of the street, but it will still have to comply with traffic laws. The second is that light rail is designed for speed and reasonably light loads, and it usually features very basic cars for passengers, not intended for the long haul.
Since light rail shares space with regular traffic, it may be slower than subways and rapid transit, which are on so-called “grade separated” tracks. These tracks run independently of the public right of way, either above or below ground, so that they are not delayed by traffic or subject to surface traffic laws. However, because light rail is above ground, it is easy to move stops around as needed, making it very convenient for passengers.
Often, electric trains are used in a light rail system since they are fast, quiet, and non-polluting. These trains may be powered with overhead cables, or through the use of a third rail. Due to safety concerns, the electric rail used in a light rail system is usually buried or otherwise secured, to ensure that people are not injured.
As with other systems which collectively make up a mass transit system, light rail is often networked with commuter rail, subways, and buses. It usually runs at set intervals or times which are often designed to mesh with other transportation systems. In most cases, the payment and fare system is also interlinked with other methods of mass transit, so that frequent riders can purchase a transit pass which covers all of the mass transit options in the city. This encourages people to use public transit, rather than personal vehicles, reducing the amount of traffic in an urban area.