Regular glass is too fragile to use as a table top unless the table top is at least a half-inch thick. Use of a table with a thin glass top risks chips, cracks and shattering. Tempered glass, on the other hand, is much stronger than regular glass. A heating process is used to make the material stronger, similar to the glass used in car windows. Glass is often used in conjunction with a wood frame to build a partially clear table.
Clear table tops made from acrylic are very durable. The strength of acrylic table tops makes them popular among companies that have tables that are used constantly. Restaurants, for example, use acrylic table tops to protect the tables themselves. Acrylic can be easily cut into any shape to make a table top to fit any type of table. It is very easily wiped clean, which adds another advantage for its use on high-use tables.
Polycarbonate is another category of plastics that is used to make clear table tops. Like acrylic products, polycarbonate is marketed under a number of different brand names. The material is somewhat subject to scratching, but it is very impact resistant. Scratches can be polished out with an appropriate scratch remover. Even under heavy use, a table top made from a polycarbonate product should not break.
Like acrylic, epoxy is a type of plastic that can be worked to create a clear tabletop. Epoxy is used in a different way from acrylic because it is a different type of plastic. Heat will melt acrylic and make it flexible, whereas heat is used during the initial hardening of epoxy and won't melt it again later. The downside of epoxy is that it is hard to get a table top as clear as an acrylic surface.