Most area rugs are wool-pile which means the rug’s pile of made of 100% wool but the warp is made from a material other than wool, usually cotton or silk. The pile of the rug is what you see and feel. The warp is the part of the rug you do not see but it is the foundation of the rug. Since wool is very soft and flexible rug weavers instead use cotton in the foundation to provide more stiffness in a rug. You can easily determine the material in a rug’s warp by examining the fringe. For more information, visit the Educational page.