Spain runs on 230 V at 50 Hz, with sockets following Types C and F. No surprises on voltage: Spain runs at 230 V, the same range as at home in the UK.
You will find identical sockets in Serbia, Andorra, Hungary and the Netherlands. Watch out when moving on: Ireland, the United Kingdom and Malta use a completely different system. In Europe, 31 of 50 recorded destinations use exactly this combination.
Protective earth
Grounded and ungrounded sockets may occur
Mixed supply: Type C without earth, Type F with earth. Which one is in your room only shows on arrival.