Asphalt shingles tend to be the most affordable, as far as material and installation costs are concerned. This is a big part of why they are one of the most common types of roof in the contiguous United States. That said, there is some variety as regards asphalt shingles in general.
In general, there are three main types of asphalt shingles. 3-tab asphalt, fiberglass asphalt, and architectural style asphalt shingles.