Moss Removal From Shingles
Roof shingles can be constructed from a wide range of materials including wood, fibreglass, cement/asbestos and bitumen. They are typically rectangular in shape. Each tile or "shake" is laid overlapping the tile beneath and covering joints thus providing a waterproof roof.
This roof moss removal help page is specifically related to bitumen based shingles as they are one of the most popular roof covering in the United States.