The gist of Portal is that you're doing puzzles. With a high tech gun that shoots portals so you can make it across pits of acid. The laboratory facility (thanks chase I was typing. now I'm laughing) is governed by a highly sarcastic robot/computer system named GLaDOS. This game is highly atmospheric, and on your first playthrough will probably become very jumpy due to the sound effect design. The end song sung by GLaDOS suggests Aperture was highly mercenary in its scientific lab purposes and everyone is probably dead because of a computer malfuction.))