A classic 2D Shoot-em up! If you played computer games in the 90s, odds are you've played this!
Overall there were about 8 levels. The designs were fairly similar, but as you progressed they became more diverse, as did the weapons. Doom is a game were bigger is better. No strategic use of weapons, just grab the most powerful one and charge through hordes of aliens. Sounds a little primitive, but it gets a hold of you.
One thing that Doom didn't have (aswell as most games from this era of gaming) was a good story. Infact, there was no (to little) story told in gameplay. If you wanted to know what you were doing there, you'd have to read the manual. Luckily story isn't required to make Doom a hit. It's a highly reccomended game and a piece of gaming history. If you can find it, buy it!
8/10, Darkside.