Warp knitting is defined as a loop-forming process in which the yarn is fed into the knitting zone, parallel to the fabric selvage. It forms vertical loops in one course and then moves diagonally to knit the next course. Thus the yarns zigzag from side to side along the length of the fabric. Each stitch in a course is made by many different yarns. Each stitch in one wale is made by several different yarns. History Credit for the invention is usually given to a mechanic called Josiah Crane in 1775. He likely sold his invention to Richard March who patented (No. 1186) a warp frame in 1778. In the intervening three years March likely had discussed the device with Morris who submitted a similar patent (No.1282) for a twisting machine for making Brussels point lace. These early machines were modifications of the stocking frame with an additional warp beam. In 1795, the machine was successfully used to make lacy fabrics. Warp frames could be used with any thread, and the warps provided a fixed anchor for the transverse threads. In 1786, Flint invented the point bar which kept the threads at a fixed distance. In 1796, Dawson introduced cams to move the bars, and regulate the twist. Brown and Copstake succeeded in imitating Mechlen net. Lindley invented the bobbin in 1799, and Irving and Skelton the regulator spring. In 1802, Robert Brown of New Radford patented the first twist-frame, a knitter that could produce wide net. Whittaker's frame of 1804 had half its thread mounted on a warp beam and half wound on bobbins mounted on a carriage. Heathcote's 1808 improvement of Whittaker's frame was essentially a warp knitting frame. The bobbin carrying beam was reduced to the same size as the machine- he called it a bobbinet. Heathcote's second patent, in 1809, was for a bobbinet that could produce wide fabrics; this was the Old Loughborough. Machine Classification In general, warp knitting machine is to distinguish between tricot and raschel by the type of sinkers with which the machine is equipped and the role they play in loop formation. The sinkers used for tricot knitting machines control the fabric throughout the knitting cycle. The fabric is held in the throats of the sinkers while the needles rise to clear and the new loops are knocked over in-between them. In Raschel knitting, however, the fabric is controlled by a