This website is a guide for how to choose/distinguish between common types of bicycles and their purposes.
Provided by Gobiking.ca (cycling in Ottawa-Gatineau), much information is provided about various bicycle styles:
Mountain, Hybrid (comfort),
Hybrid (performance/training),
Road (relaxed geometry),
Road (touring),
Cyclocross, and
Road (high performance/racing),
Additional information about frame types and gears, speeds, and components.