http://www.neatorama.com/2007/01/02/13-photographs-that-changed-the-world/
As the comments point out, calling these “photos that changed the world” isn’t exactly accurate, as the list is very America-heavy. And the accompanying text, while well written, is poorly researched. (The entire Brady blurb is erroneous, and so is the photo credit.) Nonetheless, they’re great, iconic shots, worth a look if you haven’t seen them, or a revisit if you have.