Definitions for "Headbands"
Decorative ribbons attached to the head of the spine, in medieval time head (and tailbands) were an integral part of the hand sewn construction of a book.
Strips of material (often decorative) placed at the head and sometimes also at the foot of the spine of a casebound book block.
Decorative striped feature added to protrude from the top and tail of the spine
Keywords:  berets, mop, obviously, feminine, sweat
Headbands obviously keep your long hair out of your face. They also mop up the sweat on warm days. And since men don't usually wear berets or other feminine hair restraints, the headband does the job.