In general, weaving involves using a loom to interlace two sets of threads at right angles to each other: the warp which runs longitudinally and the weft(older woof) that crosses it. One warp thread is called an end and one weft thread is called a pick. The warp threads are held taut and in parallel to each other, typically in a loom. There are many types of looms.
Weaving can be summarized as a repetition of these three actions, also called the primary motion of the loom.
- Shedding: where the ends are separated by raising or lowering heald frames (heddles) to form a clear space where the pick can pass
- Picking: where the weft or pick is propelled across the loom by hand, an air-jet, a rapier or a shuttle.
- Beating-up or battening: where the weft is pushed up against the fell of the cloth by the reed.
The warp is divided into two overlapping groups, or lines (most often adjacent threads belonging to the opposite group) that run in two planes, one above another, so the shuttle can be passed between them in a straight motion. Then, the upper group is lowered by the loom mechanism, and the lower group is raised (shedding), allowing to pass the shuttle in the opposite direction, also in a straight motion. Repeating these actions form a fabric mesh but without beating-up, the final distance between the adjacent wefts would be irregular and far too large.