A cotton ball is a soft, fiber ball that is composed of the natural material cotton. Cotton balls have an array of medical uses, like cleaning of wounds, rubbing on antiseptics to treat septic wounds, tropical ointments, cleansing cuts of any foreign material that may have entered the wound, and mopping up blood post invasive medical procedures such as an injection or blood sample collection.Sterile cotton balls reduce the risk of any foreign contaminants picked up during the manufacturing process from entering a wound that is being treated with the cotton ball.