Just wrote another feature article for Engadget Primed entitled "What is Aperture and How Does it Affect My Photos?":
Check it out- lots of solid info, links, diagrams, photos, and more - covers apertures, depth-of-field, hyper focal distance, how it relates to exposure, and so on. Now I'm working on my third piece for Engadget- one of many to come.
Causes Sean Arbabi Supports
Sierra Club, The Nature Conservancy, The Trust for Public Land