A winding machine or winder is a machine for wrapping string, twine, cord, thread, yarn, rope, wire, ribbon, tape, etc. onto a spool, bobbin, reel, etc. A winding machine or winder is a machine for wrapping string, twine, cord, thread, yarn, rope, wire, ribbon, tape, etc. onto a spool, bobbin, reel, etc. Winders are used heavily in textile manufacturing, especially in preparation to weaving where the yarn is wound onto a bobbin and then used in a shuttle. Ball winders are another type of winder that wind the yarn up from skein form into balls. Ball winders are commonly used by knitters and occasionally spinners.