At the beginning windows were only gaps in walls that were meant to let daylight into a building. However, in the course of time people started filling them with animal skins and fabrics – all that not only to provide daylight, but also to protect from unfavorable weather conditions. In time, window shutters were added that were used to open windows when the weather was favorable, or to close when the weather conditions were worse. Today windows are not only supposed to provide daylight, protect from weather conditions or ventilate rooms but also enrich the architecture of the building façade. That means that windows have been serving a decorative function for some time.
