Barcelona’s taxis are blacks and yellows with a green light on the ceiling that tells you if they are free.
They are not very expensive and are a good alternative outside the center. There you have to avoid them as it is faster to travel by Metro or walking.
Everyone should wear taximeter in sight. Two exists tariffs, urban and interurban, and after 20 hours the price of the race increases. They charge a supplement for luggage and another to enter the airport. Tips are not mandatory.
Eating, drinking and smoking in cars is prohibited inside the vehicle. You can stop them in the street or take it at the stops. There is also the service of radio taxi To request a car.