What makes Halo such a popular and supposed "great" game series?

Because it's so simpel to play. You don't need the skills that you must have for, say, Call of Duty, Medal of Honor, Counterstrike and stuff.

While the story mode for that game isn't fantastic or long, I'd have to say that the fun from the game came from the multi-player aspect for me. It wasn't seriously any better than any other game, but more or less the group that I played with made it fun. I suppose we could have had just as much fun playing some other multi-player game, but Halo just seemed to fit well with everyone. Other than that, I haven't really had a big fascination with the game.

i played halo when it came out on the pc and i couldnt judge why is it so popular in the gaming world. i thought it had a very dull gameplay. i played it 3 or 4 times and then i uninstalled from my system. maybe it became popular because people owning xbox might not have played a better FPS before.. sounds silly but i cant think of any other reason, but for me, it's just a mediocre game and there are far better FPS out there. i can't really comment on halo 2 or halo 3 because i haven't played those two games.

Im currently playing Halo 2 and plan to get some new titles as well like Lost Planet: Extreme Condition, Shadowrun and many more! Here goes, if you want to play halo 2 i recommend getting an high end dx10 video card or just a low profile dx10 vc like the one im using. you'll enjoy the graphics, like water splashing when you shoot at it.. awesome!