Braids and Knots

Because braids are strands of rope, fiber, hair, etc that are twisted together with the strands going under and over, it is not surprising that knot theorists study braids and think about knots in terms of braids.

Just like knots, braids must be finished off for mathematical consideration so that there are no loose ends that could move and change the braid (or unravel it completely) while it is being studied.

Also since braids can be arbitrarily long and quite complicated, it helps to think of them as being made from smaller parts or components.