Geotextiles are manufactured in many different ways, partly using the traditional textile procedures, and partly using procedures not commonly recognized as textile procedures. A weaving loom is a device used to weave cloth and tapestry. The basic purpose of any loom is to hold the warp threads under tension to facilitate the interweaving of the weft threads. Warp and weft are terms for the two basic components used in weaving to turn thread or yarn into fabric. The lengthwise or longitudinal warp yarns are held stationary in tension on a frame or loom while the transverse weft is drawn through and inserted over-and-under the warp. Plain weave is the most basic of three fundamental types of textile weaves. In plain weave, the warp and weft are aligned so they form a simple criss-cross pattern. The nonwoven fabric is a reliable option for any application that requires superior strength and filtration capabilities. Often used to support areas during road repair, road construction and stabilization applications, these nonwoven geotextiles feature a needle-punched exterior that allows them to effectively filter water and keep areas stable. Tensar geogrids are routinely excavated through and punched through in order to place guardrail posts, bridge piers, and underground utilities. Most geomembranes are made in a plant using one of the following manufacturing processes: extrusion, spread coating, or calendering. Calendering is the most frequently used manufacturing process. A calendered non-reinforced geomembrane is usually a single sheet of compound made by passing a heated polymeric compound through a series of heated rollers (calender).