Weaving is the oldest method of making yarn into fabric. While modern methods are more complex and much faster, the basic principle of interlacing yarns remains unchanged.

On the loom, lengthwise yarns called the warp form the skeleton of the fabric. They usually require a higher degree of twist than the filling yarns that are interlaced widthwise.
Traditionally, cloth was woven by a wooden shuttle that moved horizontally back and forth across the loom, interlacing the filling yarn with the horizontally, lengthwise warp yarn. Modern mills use high-speed shuttleless weaving machines that perform at incredible rates and produce an endless variety of fabrics. Some carry the filling yarns across the loom at rates in excess of 2,000 meters per minute.
The rapier-type weaving machines have metal arms or rapiers that pick up the filling thread and carry it halfway across the loom where another rapier picks it up and pulls it the rest of the way. Other types employ small projectiles that pick up the filling thread and carry it all the way across the loom. Still other types employ compressed air to insert the filling yarn across the warp. In addition to speed and versatility, another advantage of these modern weaving machines is their relatively quiet operation.
There are three basic weaves with numerous variations, and cotton can be used in all of them. The plain weave, in which the filling is alternately passed over one warp yarn and under the next, is used for gingham, percales, chambray, batistes and many other fabrics.
The twill weave, in which the yarns are interlaced to form diagonal ridges across the fabric, is used for sturdy fabrics like denim, gabardine, herringbone and ticking.
The satin weave, the least common of the three, produces a smooth fabric with high sheen. Used for cotton sateen, it is produced with fewer yarn interlacings and with either the warp or filling yarns dominating the “face” of the cloth.
In some plants, optical scanners continuously monitor fabric production looking for flaws as the cloth emerges from the weave machine. When imperfections appear, computers immediately print out the location of the flaw so that it can be removed later during fabric inspection.