There are many metro and bus lines so we can say the metro and bus are good in Barcelona. You can also travel with the metro FGC, trams, and RENFE trains.
If you are going to use public transportation, buy a travel card as soon as possible. A single ticket is more expensive. In Barcelona city you only need travel card one zone.
Depending on the number of trips you have planned to do you have two options: To buy a tourists travel card zone 1 (2,3,4 or 5 days): Barcelona Card which include the train to the airport, a map and some discounts or to buy a normal travel card (one zone). For exemple: T Dia – one day, T10 – 10 trips or T50/30 – 50 trips but, in this case only for one person.
For traveling by metro and bus, you can use the same travel card. In addition, for an hour and a half you will not pay again taking metro and bus, provided you do not use the same transport again. For example if I get off the metro line 1 and I take bus line 14, no payment is necessary. But if I get off the bus line 14 and again I take the bus line 14 in the opposite direction, I will pay a new trip of the card. In any case we always must use the card through the machine in all our trips.
On metro and buses in Barcelona is necessary to take care a lot with your personal belongings. Bags must be always closed. Unsuspecting tourists, as in any big city, are targeted by pickpockets.
The implementation of google maps How to Get There tells you the options to get around by public transport, by car and walking around the city.
Bus traveling advice:
In Barcelona it is necessary to stop the bus by hand. It is also necessary to press the stop button when we want off the bus. Do not wait until the last minute because the driver can continue their trip without stopping at your stop. Ask the bus driver or other passengers about your stop if you have questions. People in Barcelona are very friendly.