Warp and Weft: These are the essential elements of weaving on a loom. Fibers attached longitudinally to the loom form the warp; the weft fibers run across and through.

Flat Weave: A style made by simply weaving fibers on a loom. Flat-weave rugs lack pile.

Knotted: This method, made by tying fibers to carpet backing, is primarily associated with Oriental rugs. Generally, the greater the knot density, the better the quality. “The industry standard is 60 to 100 knots per square inch,” says Valborg Linn, a New York City rug designer.

Pile: The surface of a rug or a carpet. It is created when yarn is knotted to a backing or looped through it. Looped yarn can be cut, or sheared, which allows it to stand up, creating a plush surface. Some rugs combine cut and looped pile for a slightly sculpted surface.

Tufted: Fibers are punched into a backing and secured with adhesive. A tufted rug can have a loop or cut pile.