There are two major Tram (tramvia) lines in Barcelona.
These allow people to move between key commercial and residential areas, centers of leisure and industrial zones.
These two lines are:
The Trambaix (T1, T2, T3) starts in Francesc Macià and passes through areas such as Sant Just Desvern, Sant Joan Despí or Cornellà.
The Trambesòs (T4, T5) travels from the Vila Olympic to Sant Adrià de Besos, passing through the Fórum, ending in Badalona.
Map of Tramvia Routes: Trambaix (PDF) and Trambesòs (PDF)
Tickets and Prices
More info on: http://www.trambcn.com/