Glass

thumb|300px|A glass building facade|alt=Refer to caption

A window is an opening in a wall, door, roof, or vehicle that allows the exchange of light and may also allow the passage of sound and sometimes air. Modern windows are usually glazed, or covered in some other transparent or translucent material, a sash set in a frame in the opening. The sash and frame are also referred to as a window. Many glazed windows may be opened, to allow ventilation, or closed to exclude inclement weather. Windows may have a latch or similar mechanism to lock the window shut or to hold it open by various amounts.

solid metallic material with disordered atomic-scale structure

Vitrification (, via French '''') is the full or partial transformation of a substance into a glass, that is to say, a non-crystalline or amorphous solid. Glasses differ from liquids structurally and glasses possess a higher degree of connectivity with the same Hausdorff dimensionality of bonds as crystals: dimH = 3. In the production of ceramics, vitrification is responsible for their impermeability to water.

glass with electrically switchable opacity

special kinds of glass used for making various components of optical devices and systems

glass with additional safety features that make it less likely to break

activity to extend the life of historical objects

building material typically used as transparent glazing material in the building envelope

oven used to melt raw materials into glass