A shemagh, or a keffiyeh, is a traditiona Arab headdress that's worn by Arab men. Made from a square scarf, it protects their heads and face from desert wind and sun. It's also multifunctional - warm at night and lightweight during the day. These scarves have even become adopted by the U.S. Cavalry to protect themselves during long treks outdoors.
Check out this helpful survival tutorial to learn how to tie a shemagh/keffiyeh two different ways.