They're called Terminals. They tell you the story of how the Forerunners fought the flood, how an A.I. betrayed the Forerunners, and that the Forerunners actually did survive by using the Shield World called Onyx. Find all 7 of them and wait until the screen turns red and you're redirected to earn the "Marathon Man" achievement for 40G.
The terminals have info that shows that the Forerunners were really humans. One of the terminals shows how a Forerunner got to the Shield World and ended up in "Eden". Which I believe is where life started according to the Bible, but I'm not Christian so don't bi*ch at me if I'm wrong.
oh yeah nice job covering up the B-word... people can still tell wha it says...but whateve idc...and yeah everything SS89 said is true