There are about 50 bus lines in Nuremberg. They are meant to bring you to UBahn or SBahn stations or to outside parts of the city. If you don’t have a ticket on you, you can buy one from the driver. The bus you must always board trough the front door, so the driver can see your valid ticket.
Tickets are to buy from the driver.
If you happen to be out in late night hours on Friday or Saturday nights, there is a night bus. It drives every hour between 1 a.m. and 4 a.m. and the start point is always Hauptbahnhof (Main train station). Below is a plan of night lines.