In a woven fabric, the selvage (or selvedge) is the uncut edge of the fabric which is on the right- and left-hand edges as it comes out of the loom. As such it is 'finished' and will not fray because the weft threads double back on themselves. The term also refers to the unfinished but structurally sound edges of flat knitted textiles.
Very often fabric near the selvage is not usable as it may have a different weave pattern, or may lack pile or prints that are present on the rest of the fabric requiring that the selvage fabric be cut off or hidden in a hem. In handknitting, the selvage may be considered finished; it may also be used in seaming garments, or finished and reinforced using crochet or other techniques.
Selvage also can refer to the excess area of a printed or perforated sheet of any material, such as the white border area on a sheet of stamps.