The benefits of replacing your old windows with new ones are tremendous. New widows add to curb appeal, energy efficiency, and home security. Other benefits are that new windows can reduce sound transmission, and stabilize temperatures at more comfortable levels in the home. Since windows are a major source of heat loss in winter, and of AC-cooled air loss in summer, that means higher energy costs for you. Consequently, when replacing your windows, consider the type, the frame material, and the energy efficiency. In conclusion, there are six main types: awning, hopper, sliding, casement, fixed, and single- or double-hung. In addition, there are many types of materials used to manufacture window frames, including: aluminum or metal, composite wood products, fiberglass, vinyl, and wood.