It is cheaper to buy cafè at the bar standing (au comptoir or zinc) than sitting down (à terrace or salle). Prices also tend to be more expensive after 8pm.
Coffee is also more expensive in tourist areas for example in Paris anything near the Sacre Coeur, Opéra, the Effiel Tower, the Notre Dame and anything on the Champs-Elysée and Boulevard St-Germain near Saint-Germain-des-Près will be about €3 for an espresso - even at the bar. The normal price is €1.
There are a number of kinds of coffee. Saying simply café will produce an espresso in France.
café or café expres or expresso - short, black and strong café allongé- espresso with extra hot water café serré - extra short espresso café crème - coffee with hot milk café au lait - caffè latte, coffee with lots of hot milk cappucino - cappucino, coffee with frothy milk
For more details on dining in France see our food pages.