here you have information about it: http://spanish.about.com/cs/grammar/a/que_vs_cual.htm Basically there are two things you must know: -"qué" is used to ask for meanings, while "cuál"is used to ask for names. E.g.: ¿Qúe es Madrid? Es una ciudad. / What's Madrid? It's a city. ¿Cuál es la capital de España? Es Madrid. /What's the capital os Spain? It's Madrid. -Besides, "qué" is used to ask for something from a group of different things, while "cuál" is used to ask for something from a group of similar things. E.g.: ¿Qué tenemos que comprar, libros o discos? / What do we have to buy, books or CDs ? ¿Cuál de estos libros tenemos que comprar? / Which one of these books do we have to buy?