Historical Background

In primitive homes, the only essential opening was a door for entry and exit. The first window was probably a hole to vent smoke from cooking and heating fires. That first opening offered the same advantages and disadvantages of windows that please and plague building occupants today: it allowed indoor pollutants to escape and daylight to enter; at the same time, it allowed heat to escape in cold weather and to enter in warm weather, creating discomfort for occupants.

Shutters were eventually added. When open, they permitted light and air to enter, along with undesirable visitors, such as intruders, rain, insects, and dust. Closed shutters provided darkness as well as protection. The next addition was translucent materials such as oiled paper or animal skin, framed into window openings.

Transparent glass was first used in Roman times, allowing daylight to enter unaccompanied by unwelcome elements, and giving...