Light rail

Don't let the name fool you, these are in fact street cars, with a modern touch. Light rail vehicles are called such, to differentiate them from heavy rail trains, also known in many cities as subways, or metro. This can get confusing, as many lightrail lines run into tunnels, and are thus also subway lines.

Some cities, such as Pittsburgh, PA, never got rid off their streetcars, and simply modernized their existing system. Others, like Baltimore, converted underutilized railroad tracks into a rapid transit system.

The difference between light rail and streetcars, in today's typical transit systems, is that light rail tends to be a regionalish system with stops less frequently (maybe 12 blocks or so) except in downtown, while streetcars are a local transit system that operates a lot like a bus. Portland, Oregon has light rail (MAX) and is building a streetcar. The light rail line runs some 33 miles from the suburbs to downtown, while the streetcar runs about 3.5 miles from an inner neighborhood to downtown, with stops every 2-3 blocks or so.