If you, say, wanted to get from Regent's Park station to Great Portland Street, the Tube map would tell you: take the Tube, go to Baker Street, change over, take another Tube.
Certo? Se você, digamos, quer ir da estação Regent Park para a da rua Great Portland, o mapa dirá, para pegar o metrô, ir à rua Baker e baldear para outro metrô.