In layman’s terms, glass is understood to refer to the manmade silica-based material used to make such items as window panes, bottles and drinking vessels. To the materials scientist, however, the term glass refers to a specific state of matter, often called the ‘glassy’ state; its defining property is that, regardless of its chemical composition, the material has solidified from the liquid state without forming any crystals, and thus at the atomic level lacks the regular ordered structure of normal crystalline solid materials. The ‘glassy’ state of matter is therefore the random, three-dimensional network of atomic bonds in the liquid state, which is preserved in the solid state; glass is therefore sometimes described as a ‘super-cooled’ liquid. It is a truism of science therefore that almost anything can be made into a glass if it is cooled down fast enough from the liquid state to prevent the formation of crystals as the material solidifies; the required rate may very well be measured in millions of degrees per second.