Spain uses the euro (symbol: €), code EUR.
Banknotes come in denominations of 500, 200, 100, 50, 20, 10 and 5 euros. Euro is subdivided into 100 cents. Coins come in denominations of 2 and 1 euros and 50, 20, 10, 5, 2 and 1 cents.
Note that while euro coins each have a national side (indicating where they were minted), they are perfectly good in any country that uses the euro currency.
Currency name, symbol, ratio (subunits), code and it's denominations (both as banknotes and coins). Exchange rate is coming soon.
Currency category is available in production API version 2.