Before your get set to cut and sew, there are some things you should know about your fabric. Only you will be able to determine with assurance how much fabric a project requires. Knowing a few simple terms will be helpful in completing your decorating projects. Usable width refers to how much of the fabric's width you will be able to utilize for your project. It may or may not be the same as the fabric's actual width.
Selvage refers to the finished lengthwise edges of the fabric.
They also will not ravel. On home decorating fabrics with a printed design, rather than one that is knitted or woven into the fabric, the motif usually does not extend into the selvage area. Instead, the name of the manufacturer and information on any special finishes may be printed along this edge. If the selvages are tightly woven, using them as seam allowances can distort your project. Most of the time it is better to cut them off.