Hand-knotted rugs are also commonly made with multiple kinds of material. A mixture of wool and silk is very popular in hand-knotted rugs. A rug made out of these two materials is predominately woven with wool while the silk is woven in periodically to add a luxurious touch to the final product.

Knot density could be a factor in the value of a rug, but this is not always true. In nomadic and some village items, knot density is usually not a factor. It is not a factor for collectors of these rugs either because nomadic and village rugs are judged by different standards than workshop rugs. Nomads and village groups do not have the same sophisticated tools as other city weaving groups. Their items are valued by the fact that their designs are created from memory.

Pile-woven or knotted rugs are created by knots. Most handmade rugs with the exception of kelims are woven by tying knots on the warp strands. The type of knot used in weaving and knot density are discussed below. Carpet and rug knots are the basic building blocks of these type of exclusive and exquisite artworks.