How do FRP’s use fiberglass?

First, the manufacturer gathers fiberglass fibers into bundles like strings of yarn. These bundles are then combined to create what is called a "roving." Rovings are a continuous rope, like a twine made from fiberglass fibers. FRP's are made from rovings that are either chopped into short strands or woven into cloth of varying thickness and density. To make a fiberglass or part or component the fiberglass material is impregnated with liquid resins and then either sprayed into a mold, drawn through a die, hand laid into a mold, or wrapped around a plug to give the product its desired shape. Through different processes such as heat or chemical reactions, the FRP is hardened into a solid piece that will hold it's shape after being removed from the mold or plug. The part is then trimmed, sanded, finished, and painted or gel-coated.