Light rail or light rail transit ( LRT ) is a form of urban rail public transportation . Generally it can carry less people and has a lower speed than heavy rail and metro systems , but it can carry more people and has a higher speed than street-running tram systems . Light rail or light rail transit ( LRT ) is a form of urban rail public transportation that generally has a lower capacity and lower speed than heavy rail and metro systems , but higher capacity and higher speed than traditional street-running tram systems .