Glass that is used as a building material. It is most typically used as transparent glazing material in the building envelope, including windows in the external walls. Glass is also used for internal partitions and as an architectural feature. When used in buildings, glass is often of a safety type, which include reinforced, toughened and laminated glasses.

Glass is a material made from liquid sand.  This means that materials transform from a hard and brittle state into a molten state, or vice versa depending on whether the glass transition temperature is the melting or solidifying point. An amorphous solid has some of the crystalline order of a solid and some of the random molecular structure of a liquid.

Glass is a very commonly used material because, whilst still molten, it can be manipulated to into forms suitable for a very wide range of different uses, from packaging and household objects to car windscreens, glazing and so on.