The underground Metro system in Paris is huge but it is easier to use than its counterpart in London.
Paris Metro Tickets
One ticket covers one journey, whether you travel for one stop, twenty stops, change trains or fall asleep and wake up at the end of the line. That’s simpler than London because you don’t need to worry about zones.
Paris Metro Lines
One train will call along all the stops on its line. The lines are given a number and a colour (although the colour can vary quite a lot between stations so it is safer to use the number.)
Direction is given by the station at the end of the line. For example, Line 1 (the most popular one for visitors) runs between La Defense at one end to Château de Vincennes at the other, so a metro station will have one platform labelled La Defense for trains running in that direction and another labelled Château de Vincennes for the train in the opposite direction.