Dhow

A dhow is a traditional boat design with a triangular sail, called a lateen[?]. It is indigenous to the coasts of the Arabian Peninsula, India, and East Africa.

They also often incorporate a kamal, a navigation device that determines latitude by finding the height of the Pole Star above the horizon.

Further information:

http://www.archaeology.org/9705/abstracts/dhow.html

http://www.ecssr.ac.ae/Land/Dhow.html