This is a comprehensive list of all the lines operated by the Catalan government-owned Ferrocarrils de la Generalitat de Catalunya rail company, ordered by type.
The FGC suburban lines is the collective name given to the suburban metro network that serves the Barcelona metropolitan area and is fare-integrated with most of the other ATM transport services in the city. They're operated by Ferrocarrils de la Generalitat de Catalunya and sometimes are considered part of Rodalies Barcelona. These are all S-prefixed (after suburbà):
Part of the cercanías commuter train system in R-prefixed (after rodalies) just like the rest of Rodalies Barcelona lines:
These are L-prefixed, just like any other metro line in Barcelona: