Asphalt shingles (known in the industry as composition shingles) are the most common materials used on roofs in North America. Early versions of these shingles were made with an organic base mat of felt, paper, or wood pulp, which was then coated in asphalt and topped with a layer of ceramic granules. Thanks to new technologies, these shingles have been replaced with a fiberglass base reinforced with synthetic resin, coated with asphalt and topped with granules. The resin and asphalt make the shingle waterproof and hold the granules in place, while the granules protect the shingle from UV damage, add color and can help resist algae and fungus growth depending on what additives are added by the manufacturers.