Prague’s public transport system is great. Apart from the trams and metro, you’ve got the bus. They’re what you should plan on using if you’re travelling outside of the city centre, given that they’re not really immune from traffic congestion in the centre.
These handy buses run from 5.00 a.m. until midnight and use the same tickets as the ones you’ll use on the tram and underground.
If you’re about to arrive late at the bus stop, take it easy and don’t run – it’s probably already gone. Apparently in Prague the bus takes off before its scheduled departure.