Greek and English are the main languages spoken here. (Random fact: after all the math and physics courses I have taken while working towards a mechanical engineering degree, I pretty much know the entire Greek alphabet). Fortunately, we have some friends who live in Greece, and they did all the speaking and translating for us.
Greece is a part of the European Union so the currency here is the Euro! (€)
The average cost is around 1€ per bottle, but in popular, touristy destinations like Athens or Aegina, it can be more expensive. In these places, tourism often provides a significant source of income, so you will experience a lot of sneaky tactics designed to "encourage" your spendings. If you're not careful, you can easily spend 3-4 € on just water at one meal.
For example, we were told by a waiter that if we ate there, we would receive free appetizers and dessert. He then proceeded to ask if we wanted to have a Greek salad as an appetizer. When we questioned further, we discovered the real free appetizer was a different "black-eyed peas" dish. Feeling accomplished that we avoided one such scheme, we didn't think when the waiter brought out bread and bottled water (which we had not asked for) for our table.
