Filler cord covered with fabric and used to trim edges or seams. General sewing term.

Piping cord covered in fabric and sewn around the edges, often into the seams, of tiebacks, valances, curtains, etc., for decoration.

In furniture this term means the strengthening of a seam by the use of piping, which may or may not have cord, which is sewn into the seams of a cushion, increasing the durability.

In knitting, welting is the horizontal analog of ribbing; that is, one or more horizontal rows of knit stitches (as seen from the right side) alternating with one or more rows of purl stitches (also as seen from the right side).