Add structure or bind seams with Twill Tape Trimming. Twill is characterized by its textile weave, a pattern of diagonal parallel ribs. This is different than that of a plain or satin weave. Twill weave is an ancient weaving technique, and due to the structure of twill, it drapes quite nicely. Bind the seams of a Chanel style blazer with twill tape trim, or add structure to a twill skirt.