Asphalt shingles are composed of the following:
1) a base material, either organic felt or glass-fiber mat, that provides support for the weather-resistant components and gives a shingle strength.
2) asphalt and fillers.
3) surfacing material, generally in the form of mineral granules, that provides protection from impact and UV degradation and improves fire resistance.
Shingles may be produced in a single layer or two or more layers. The latter generally are known as laminated strip shingles, or architectural shingles, and they have a three dimensional appearance.