Extras in Halo 3?

[Good for somethin']

What is the significance of all of the terminals scattered throughout Halo 3? I only found one and I didn't get it.

 

[capt. blumpkin]

it is for the marathon man achievement. there are 7 terminals. they are ancent forerunner messages and if you want to get the achievement...

http://www.youtube.com/watch?v=I-8dnEqAVaY

 

[Dylon]

if you find the 7 on the last 3 levels (not including Cortana) you will get marathon man

 

[Brandon S]

There are 7 of them all located in the covenent,arc and so on. the one in cortana is useless. Its for the marathon men achievement.