A drawstring (draw string, draw-string) is a string, cord, or rope used to "draw" (tighten) or tie closed an opening in fabric or other material. Typically, the drawstring is loose when not being used, and tightened when needed during use. For the bags, an aglet is usually (but not always) at the end of a drawstring to prevent unravelling, and a cord lock can be used on a drawstring to keep it taut.