There are two official languages in Catalonia: Catalan and Spanish, and there are more and more people in the region who understand and speak English. You're sure to get by.
Catalonia has its own language: Catalan. Most of the people who live in Barcelona are bilingual and speak Catalan and Spanish, which is also an official language. Street names and most road and transport signs are in Catalan..
Many restaurants, especially those in the city centre, have menus in several languages. But if there's something you don't understand, don't be afraid to ask, people will be only too happy to help. Many people from Barcelona understand English and French.
Here are some of the most frequent Catalan expressions translated into Spanish, English and French, which will help you get around the city. Look up a word or expression: Pdf vocabulary list.