Sisal is a species of flowering plant native to southern Mexico, but widely cultivated and naturalized in many other countries. It yields a stiff fibre used in making rope and various other products. The sisal fibre is traditionally used for rope and twine, and has many other uses, including paper, cloth, footwear, hats, bags, carpets, geotextiles, and dartboards. It is also used as fibre reinforcements for composite fibreglass, rubber, and concrete products. It can also be fermented and distilled to make mezcal.

Fiber or fibre is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate fibers, for example carbon fiber and ultra-high-molecular-weight polyethylene.