Tapas are small dishes eaten with a drink. Going from bar to bar for a drink and a bite — ir de tapas or ir de cañas — is one of Spain's great social habits, very often standing at the bar.

Spanish	English
una tapa	a small portion, often served with a drink
una ración	a full plate to share
media ración	a half portion
una caña	a small glass of draught beer
un vino / un tinto	a glass of wine / of red wine
las patatas bravas	fried potatoes with a spicy sauce
las aceitunas	olives

In Granada, famously, many bars bring a small tapa free with every drink — and quite a few bars in Madrid put a little something down with yours too.