In this sense, LRT is London Regional Transport: the public body that used to run London’s buses and Underground (and later the Docklands Light Railway too). It was set up in the 1980s, when the national government took London’s transport away from the old city council, and it lasted until about 2000, when Transport for London (TfL) took over under the new mayor. You will still meet LRT on old tickets, signs, maps and papers; it is an organisation’s name, not a kind of train. Though actually, those same three letters mean something else in many cities today — a light railway — and that is probably the LRT a Taiwan student meets first.