Amnesia or Penumbra? Which should a person play first? (No spoilers please)

Aside from being developed by Frictional Games, the game worlds are not connected.

Both series are worth playing, but I would personally play the Penumbra games before Amnesia, simply because they were made first. The choronological order of the Penumbra games is Overture, Black Plague, Requiem. I enjoyed Black Plague the most, followed closely by Overture, and Requiem last because it was only puzzle based :/

Amnesia The Dark Descent is a work of art, so save the best until last!

I'd say Penumbra just for a single reason.
Amnesia is more well done, so passing from Amnesia to Penumbra is harder than the reverse.
Storywise it doesn't matter because the stories are different. The only thing similar is the fact that they are made by the same studio, hence the gameplay is more or less the same.

Both have different stories so no mater which you play first.

Penumbra first! amnesia is better and the story line is longer + custom stories. it would be better to prepare yourself with the penumbra games. They were all most enjoyable anyways.

Penumbra series first.

(But be sure to play BOTH series!)

I've only played Amnesia and I give it a great review!

Start with Penumbra cuz its less "scary" that Amnesia. So Penumbra will prepare u for more.

I have bought all the penumbra games. Can't wait to play trough them. Got some hours into the first one and I thought it was great. But now I have to start all over again as that save file is on another computer.

Personally, I enjoyed Penumbra more. Interaction mechanics were better and it was far scarier than Amnesia. Amnesia for me felt like a dumbed down remake of Penumbra which was missing much of what made Penumbra great.

In Penumbra, you can kill the enemies!

I have played them all and I honestly don't see what the fuss is about Amnesia :/ I absolutely loved Penumbra, but Amnesia seemed more... dumbed down physics wise, which is what I enjoyed most about Penumbra. Amnesia is more plot based though, less physics puzzles. I've never done any custom maps/mods/whatever for either of the games though...