I am from Moscow, and this is a large city, where you spend most of the time in the metro while trying to get from one end of the city to another. However, this is a little bit different in Prague.
In my opinion, the most popular transportation here are trams and people do not use underground that much. Anyway, the underground has a special life, too. Homeless people trying to sleep in the underground carriage, drunk students trying to get to their dormitories at 6 am from a party, and office planktons trying to get to their offices. Also, we cannot forget about the style and architecture of every station: some stations are sparkling and look like they are from another planet, and some are just boring and trashy. Every station has its’ own city life, which is hard to understand for people from small cities.