Composite windows can mean a variety of different things to different manufacturers, but generally come in two basic types—fiberglass and a wood/plastic composite. The newer type of composite window that is becoming available uses chemically–bonded blends of wood and plastic resins, and there are even versions made from a blend of wood chips and recycled plastic. However, with the exception of fiberglass, most composite frames are fairly new to the market, and as a result, there is no conclusive evidence to determine how these materials hold up over time.