I agree and disagree simultaneously. From a quick glance, they highly resemble each other. But, when you start to break down the mechanics of each game, they are clearly different. Both are first person shooters. However, Halo is primarily a military science fiction game. Doom is sort of a space marine operation under the Union Aerospace Corporation that fights hordes of demons. Halo involves an interstellar war between humanity and unknown alien type creatures (called Covenant). Personally, I got bored from Halo gameplay very quick. I did like the 4th installment in the Halo series (in my opinion the best of the Halo series). All around, however, I'm more of a Doom guy. But truly it comes down to the preference of that individual.
There really is a lot of similarity between DOOM and HALO, but it stops right there because the games have different proposals. But if we stop to think, is it really possible to create something today that doesn't resemble something else that already exists somewhere else? I think it's impossible.
Not really. They might look similar because they are both FPS, but in my opinion they are very different games with different purposes. Doom is more horror than sci-fi, while Halo is just pure sci-fi. They have different styles, and the monsters and weapons of one wouldn't fit at all in the other. You shoot at enemies, and this is where the similarities end for me.
