What?! You've never heard of the Portal games before? You have to be very young then
Have you ever heard anybody saying ''cake is a lie''? that phrase comes from the Portal 1 game. You really should go play it and get to know the famous GlaDOS. She will take a very good care of you.
In all seriousness though. The Portal games are really one of the best puzzles type games out there. Without spoiling too much - the concept it really simple. You will be given a ''portal'' gun that can fire two different type of portals and using it you have to try to beat an insane amount of levels to reach ''the end''. You can even play it with your friend. Just don't expect it to be easy. Some levels can take a long time to figure out!