TechniqueWarp threads strung on a pile loom. Source: Wikimedia Commons
The vertical foundation threads held under tension on the loom. They run the length of the rug and become its fringe.
The warp is the set of vertical foundation threads strung tightly on the loom before any knotting begins. They run the full length of the rug, and each row of knots is tied around pairs of them. Where the pile ends, the warp threads continue and are gathered into the fringe.
Warp is usually strong cotton or wool. On a nomadic ground loom the warp tension shifts a little as the camp moves or the weather changes, which is one reason a handmade rug carries faint, organic irregularities in its geometry.
