Floor coverings include carpets and rugs made from natural or synthetic fibers. Carpet weaving has a long tradition in India, where it is now the world's largest producer and exporter of handmade carpets. Common carpet styles include berber, cut-n-loop, plush, cut pile, frieze, multi-level loop, and shag. Nylon is most commonly used but other materials include polypropylene, wool, polyester, and acrylic. Carpets are classified by their construction method such as woven, needlefelt, knotted, or tufted. India exports carpets worldwide, with the US as the largest market, though it faces competition from other producers.