The term cathedral glass is monochromatic sheet glass, which may be textured on one side. Traditional cathedral stained glass was created with a mixture of natural dyes, minerals, lime, and urine, which was then baked on to the interior side of the glass as a sort of glaze to provide color. Modern day stained glass has the dyes melted and mixed in to the glass itself, rather than simply being applied as an inside coating. Cathedral glass, or stained glass was traditionally used to decorate the interior of churches by filtering the light in to different colors. The upper chapel in the Sainte-Chapelle in Paris, France is perhaps the most famous and elaborate of all cathedral glass works.
Stained glass would not have gained the notierarty if not for the advent of gothic style architechture, which transmits the vertical load of the building to pilliars outside the walls, known as flying buttresses , allowing for the traditionally thick walls to be opened up greatly, thus allowing many times more area of the wall to be devoted to cathedral glass and the stories that could be told with the images created by it.