Arabic is the official language, although English is widely spoken and most road and shop signs and restaurant menus are in both languages. The further out of town you go, the more Arabic you will find, both written and spoken. Arabic isn't the easiest language to pick up, or to pronounce, but if you can throw in a couple of Arabic words here and there they will be warmly received.
Useful phrases: Greetings
Useful phrases: Asking for help and directions