All these images were captured and taken during the testing & development duration of Halo 2, these test are commonly referred to as the alpha or beta stages of the game. From these images you can see how certain features in the game evolved into the final product you play today, and some that didn’t make it but shipped with Halo 3.
I just uploaded a bunch of Screenshots & Captures that were over at Halomods.com that show off some of the current Halo 3 Modifications going on at the moment, they’re pretty damn cool! Anthony has managed to locate the values in the 360 executable file that allows him to execute debug commands such as wireframe which you can see in the screenshots, Veegie has modified the game so that it allows him to play as an ODST Marine in the single player campaign which also looks very cool! Check out the custom melee animations also.