A carpet is any loom-woven, felted textile or grass floor covering. The term was also used for table and wall coverings, as carpets were not commonly used on the floor in European interiors until the 18th century. The hand-knotted pile carpet probably originated in Central Asia between the 3rd and 2nd millennium BC. Carpet-making was introduced to Spain in 10th century by the Moors. The Crusades brought Turkish carpets to all of Europe, where they were primarily hung on walls or used on tables. Only with the opening of trade routes in the 17th century were significant numbers of Persian rugs introduced to Western Europe.
Some use the words carpet and rug interchangeably. Historically, however, some have distinguished between carpet and rug based on size (the former being larger) or use (carpets on floors, rugs on beds or on the hearth). For the sake of clarity, some textile scholars also differentiate between carpets and carpeting. In this usage, the latter are wall-to-wall and are often woven or tufted as "roll goods", most often in 12 foot widths but sometimes in up to 15 foot widths. In the real estate and home improvement industries a distinction is made between carpet (or carpeting) and rug. The former indicates a covering that is affixed to a floor and the latter a floor covering that is loose-laid, most often for decorative purposes.