Muslin fabric is a type of woven cotton material that quilters often use as a background fabric. It usually costs less than other cottons. Muslin fabrics comes in two “flavors”; unbleached (beige in color) or bleached (white). It is also available in different widths (not always 45 inches) so be careful to check this out before your purchase. 90 inches or larger muslin makes a nice backing for a larger quilt because it does not have to be pieced. Muslin fabrics also comes in different weights and thread counts. The heavier muslin fabric is more suitable for quilting. The lighter weight is often woven loosely and hard to handle.