Rapid transit in Germany consists of five U-Bahn systems and fourteen S-Bahn systems. The U-Bahn or Untergrundbahn (underground railway) are conventional rapid transit systems that run mostly underground, while the S-Bahn or Stadtschnellbahn (city rapid railway) are hybrids of rapid transit and commuter rail that run underground in the city centers and above ground in the suburbs. There are also eighteen premetro or Stadtbahn systems that are rapid transit in the city center and light rail outside.
The U-Bahn consists of five systems: in Berlin, Frankfurt (only line U4), Hamburg, Munich and Nuremberg; these are all run by the transit authorities in the city.
The thirteen S-Bahn systems are in Berlin, Dresden, Hamburg, Hanover, Magdeburg, Mitteldeutschland, Munich, Nuremberg, Rhein-Main, Rhein-Neckar, Rhein-Ruhr (parts thereof also trademarked as Rhein-Sieg and/or Cologne), and Stuttgart. The S-Bahn systems are all franchised to the incumbent train operating company Deutsche Bahn, and have developed from the mainline railways. Normal headway is 20 minutes and use dedicated tracks running alongside mainline routes. Ticketing is governed by the local transport authority (Verkehrsverbund) and connectivity is integrated into the city public transport system.