It is very difficult to talk about The Stanley Parable without spoiling any single little thing, but I'll do my best here. TSP is a first person experience. You walk around with WASD and can interact with things using the E button. There's a narrator that talks over the things you do and the things you should be doing. Then you win (?)
This game is funny, the jokes might not be funny if you hear them multiple times, but then again maybe they still are sometimes. This game also didn't last more than 3-4 hours, but I'm happy with that. Great writing and wit can carry you so far, it would've been less fun to play if it had gone much longer, because the gameplay wasn't it's strength. Or was it? Sometimes it was.
Each character has multiple stats, HP, damage per gem (the amount of damage they deal when you match specific gems), and multiple skills. You can finish the game really quickly if you follow the critical path, but some of these alternate ones are really involved and you go through multiple choices, the only thing you can think about is to try the other choices when you're done with this one. You can raise their level up to the combined level of their skills by using the 'free' currency, and you can raise skill levels with comics or currency.
And sometimes the game is a bit too transparent, sometimes you know that it knows that you know, but most of the time you're going to be surprised, baffled and entertained. I would recommend you to play The Stanley Parable, yes, You.
It is very easy for The Stanley Parable to talk about you by spoiling everything, but it will do it's worst here. You are a real person. You push keys on your keyboard. There's a voice that tells you funny things that make you laugh and think. Then the game wins (!!!)