Sufism is the mystical side of Islam.  The name comes from the woolen robes of it's followers who aspired to a divine experience through poverty and self denial.

Of the many Sufi sects, the most famous is the Mevlevi, or Whirling Devishes

The Dervish enter the sema hall (above) led by the semazenbashi or dance master and line up to one side with heads bowed.  The Sheik is the last to enter, bowing he walks slowly to his post and takes up his position on the red sheepskin rug.  He stands, bows and begins to walk around the hall.   

The Dervish follow the Sheik, stopping to bow to each other at the post.   They circle the dance floor 3 times at which point the last Dervish bows to the Sheiks post and returns to his place as the Sheik takes his post.