Like in all three Baltic states trolley busses (which have become pretty rare throughout the western Europe) belong to the city of Vilnius, Lithuania. In addition there is a large fleet of normal busses that you can use to travel around. Since 2001 the construction of a metro system with three lines connecting the busiest spots is discussed – but work hasn’t started yet.
If you want to take a bus you can go to a limited number of kiosks to be electronically readable tickets. Or you take the easy way for tourists and just go to the driver to buy a ticket for one Euro. You get a tiny slip of paper that you have to invalidate in a machine next to the driver. Thanks to the assistance of Google Maps travelling by bus is easy and fun in the capital city of Lithuania.