S-Bahn
S-Bahn ( ESS-bahn, German: [ˈɛsˌbaːn] ; lit. 'S-train') is a type of hybrid commuter rail and rapid transit service, originating in German-speaking countries. In general, S-Bahn systems link suburbs with the city centre at moderate speeds, while continuing across the urban core over a central high-frequency corridor where multiple lines converge, where they provide a rapid means of travel across the city.