Fiberglass is a material made of thin glass threads that is used for insulation and reinforcement. There are two main types: S-glass, which is high strength but expensive, and E-glass, which is weaker but more affordable. Fiberglass is used in many industries like automotive, textiles, and construction. It is durable yet lightweight, with applications in car parts, clothing, and sports equipment. Fiberglass melts at 1121°C but remains an effective insulator even when heated.