Cedar typically - there's a house around the corner for me that has genuine cedar shingles on the roof and another with cedar shingles on the walls. Lots of houses back East have cedar shingle walls (exterior)
Nowadays most roofs use asphalt shingles - basically some kind of fabric covered with an asphalt/grit layer.

That belt pulley video was awesome - I could sit there and watch that spin all day long - need more of a close-up though : )