Glass-reinforced plastic (GRP), is a composite material made of a plastic reinforced by fine fiberss made of glass. The plastic is most often polyester, but other plastics, like epoxy, are also sometimes used.
GRP is a versatile material with many uses. Its first main application was for building of boats, where it gained acceptance in the 1950s, and now plays a dominant role. But its use has broadened over the years, and it is used extensively within the automotive and sport equipment sectors.
The term "fiberglass" is often used, rather imprecisely, for GRP.