What does 'knots per square inch' mean?
"Knots per square inch" refers to how many knots are packed into a square inch. Single knotted rugs have two strings in the same space and double knotted rugs have four strings; hence twice the amount of knots. More knots per square inch does not make it a better rug. The rugs are just made with different techniques, with the same basics applied such as materials and skill level. If the materials used to create a rug are good and there is good craftsmanship then the rug will be good.