ground weft vs. pattern weft

The ground weft weaves with all of the warp ends to form the ground cloth. In tied unit weaves, the ground weft weaves plain weave (the ground cloth can aso be twill or satin) with all of the warp ends. The pattern weft creates pattern by floating above groups of warp ends (or beneath them) interweaving with only the tie-down ends. (The main weft in lampas is sometimes called the ground weft and the main structure the ground structure. The secondary weft in lampas is sometimes called the pattern weft.)