Rufiyaa. Exchange facilities in the airport, banks and hotels offer very similar rates. Many hotels will accept card payments too. The Maldives is an expensive place to visit, particularly if you wish to travel around some of the islands, so make sure you have enough cash with you. US$ are most widely exchanged.
Dhivehi is the official language of the Maldives, but English is widely spoken in the resorts as is German, French, Italian and Japanese.
+960 for the Maldives, there are no other codes for the different towns.
The main dangers in the Maldives come from the sea. The currents in the sea can be quite strong, so pay attention to any warnings about this and don't dive alone. Heatstroke can be a big problem, especially if you're wearing a wetsuit all day and not hydrating properly so take regular breaks.
Everybody gets a free 30-day visa provided that they have a return ticket booked, and proof of funds. Proof of funds can either be a reservation for a hotel or a minimum of US$25 per day. Importing alcohol, pork or pornography is forbidden.