Cotton Cheesecloth and Butter Muslin are used to drain curds. Butter Muslin has a slightly closer weave than Cheesecloth and is typically used to drain soft cheeses. They are reusable and both should be cleaned in the same way. After using cheesecloth, rinse it in cold water. If you have curds stuck in the fiber, rinse with whey which helps loosen the curds prior to rinsing with water. Then wash it right away occasionally adding a little bleach to the water. Boiling the cheesecloth in water to which a little washing soda has been added will help maintain freshness. Washing soda can be found in the laundry detergent aisle in the grocery.
Using cheesecloth found in the grocery store is risky. It is not woven tight enough to contain the curd. It would be sad to loose your cheese through the wide holes. If you are caught in a pinch and cheesecloth from the grocery is all that is available, always double it. It will probably not be suitable for reuse.