<P> Warp and weft are terms for the two basic components used in weaving to turn thread or yarn into fabric . The warp yarns are held stationary in tension on a frame or loom while the lengthwise or longitudinal weft (sometimes woof) is drawn through and inserted over-and - under the warp. . A single thread of the weft crossing the warp is called a pick . Terms vary (for instance, in North America, the weft is sometimes referred to as the fill or the filling yarn). Each individual warp thread in a fabric is called a warp end or end . </P> <P> Inventions during the 18th century spurred the Industrial Revolution, with the "picking stick" and the "flying shuttle" (John Kay, 1733) speeding up production of cloth . The power loom patented by Edmund Cartwright in 1785 allowed sixty picks per minute . </P> <P> The words woof and weft derive ultimately from the Old English word wefan, to weave . Warp means "that which is thrown away" (Old English wearp, from weorpan, to throw, cf . German werfen, Dutch werpen). </P> <P> The warp is the set of yarns or other elements stretched in place on a loom before the weft is introduced during the weaving process . It is regarded as the longitudinal set in a finished fabric with two or more sets of elements . </P>

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