Warp and weft are the two basic components used in weaving
to turn thread
. The lengthwise or longitudinal warp yarns are held stationary in tension on a frame or loom
while the transverse 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'').
[Barber (1991), p. 79]
Each individual warp thread in a fabric is called a ''warp end'' or ''end''.
[Burnham (1980), pp. 170, 179]
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.
The word ''weft'' derives from the Old English
word ''wefan'', to weave. ''Warp'' means "that which is thrown away" (Old English
''wearp'', from ''weorpan'', to throw, cf. German
The warp is the set of yarn
s or other things 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.
The term is also used for a set of yarns established before the interworking of weft yarns by some other method, such as finger manipulation, yielding wrapped or twined structures. Very simple looms use a spiral warp, in which the warp is made up of a single, very long yarn wound in a spiral
pattern around a pair of sticks or beams.
The warp must be strong to be held under high tension during the weaving process, unlike the weft which carries almost no tension. This requires the yarn used for warp ends, or individual warp threads, to be made of spun
and plied fibre
. Traditionally wool
, and silk
were used. However, improvements in spinning technology
during the Industrial Revolution
yarn of sufficient strength to be used in mechanized weaving. Later, artificial or man-made fibres
such as nylon
While most weaving is weft-faced, warp-faced textiles are created using densely arranged warp threads. In these the design is in the warp, requiring all colors to be decided upon and placed during the first part of the weaving process, which cannot be changed. Such limitations of color placement create weavings defined by length-wise stripes and vertical designs. Many South American cultures, including the ancient Incas and Aymaras, employed ''backstrap weaving'', which uses the weight of the weaver's body to control the tension of the loom.
[''Weaving in the Peruvian Highlands'', Nilda Callanaupa Alvarez]
Because the weft does not have to be stretched on a loom the way the warp is, it can generally be less strong. It is usually made of spun fibre, originally wool
and cotton, today often of synthetic fibre such as nylon or rayon.
The weft is threaded through the warp using a "shuttle
", air jets or "rapier grippers". Handlooms were the original weaver's tool, with the shuttle being threaded through alternately raised warps by hand.
The expression "warp and weft" (also "warp and woof" and "woof and warp") is used metaphor
ically the way "fabric" is; e.g., "the warp and woof of a student's life" equates to "the fabric of a student's life". Warp and weft are sometimes used even more generally in literature to describe the basic dichotomy of the world we live in, as in, up/down, in/out, black/white, Sun/Moon yin/yang, etc. The expression is also used similarly for the underlying structure upon which something is built. The terms "warp" and "woof" are also found in some English translations of the Bible in the discussion of mildews found in cloth materials in Leviticus 13:48-59.