Although the Cannes Film Festival may be the most-documented film event in the world, it's a tough one to capture. Red-carpet mayhem at the Palais is real, but it doesn't occupy that much real estate. Most of the French commune is occupied with people who are trying to get close to said glamour.
Much of the weirdness stems from the Cannes market, which sells thousands of titles that would never have any hope of getting into the festival, and the tourists who come to Cannes to look at the celebrities -- or, more likely, look at the people who are looking at the celebrities.
So: Here's a photographic Cannes primer, which provides something of a core sample of what you really might expect to see on the Croisette.