Tempered glass or toughen glass is also referred to as Safety Glass. The tempering process strengthens the glass, and if broken, Tempered glass, crumbles into small granular cubicle pieces. This eliminates the danger of sharp edges. Due to the strength and safety features associated with tempered glass, it is used for shower doors, skylights, table tops, and where greater risk might occur. Automobile side and back windows use tempered glass.