Selvage edge refers to the outside edges of fabric as it comes from the bolt. These edges may also be referred to as "selvaged edges" or simply as "the selvage". When fabric is manufactured, or loomed, the edges are attached to the loom by its edges.
If a pattern is woven into the fabric, the pattern will not continue onto the selvage edges. If the fabric is printed, the printed pattern will not appear on the selvages. Some of the component colors of the print will likely appear on the selvage in small squares or dots.
There is also likely to be written information printed on the selvage edge; this information typically identifies the manufacturer and the fabric by name or by product number.
Important Purposes of the Selvage Edge
The selvage serves several very important purposes to the consumer. First, the selvage is a finished edge that will not fray, allowing the fabric to be handled easily. The selvage also provides a reliable straight edge.
You can rely on the straight edge of the selvage when aligning your pattern pieces before cutting with the grain, or direction, of fabric. Thus, when the pieces are assembled, they will appropriately all follow the grain.
However, your pattern pieces should not overlap the selvage; rather, you should cut away from the selvage edge after placing your pattern on the fabric, so that the selvage does not appear in your completed piece.
You can also use the printed information on the selvage to identify the fabric to others, to obtain additional fabric from the manufacturer or store, or to learn about similar fabrics in the same product line