You'd be amazed how awesome Portal is, just a shame that it's a very short game indeed.
It doesn't really have much of a story; you're stuck in an Enrichment Centre for Aperture Laboratories, also known as Aperture Science which is the fictional research corporation responsible for the creation of the portal gun. You play a silent protagonist named Chell, you wake up and you hear a robot named GLaDOS who guides you and tells you what's up ahead.
Gameplay: It may be a first-person shooter but it's actually more of a puzzle-solving game, using the mouse to look around, W to go forward, A for left, S to move back and D for right, E is also used to active a switch.
Just after you walk around and knowing what's going on here, you'll pick up a Portal Gun which can let you create portals, but you can only have 2 portals.
If you fire one at a wall in front of you a portal will appear, if you fire another one somewhere else like the celling, you can go through the portal through the wall and you'll end up falling from the ceiling. The left click button to make a blue portal and the right click button to make an Orange portal, which ever Portal you use first either blue or orange you'll end up coming out of the other one.
Another thing you'll encounter is that you can pick up stuff with your Portal Gun; you can carry objects or heavy cubes. Reason for this is because there will be red button switches to open doors but you need something to hold the switch and a way to get through.
Graphics and Sound: Isn't much to say on its graphics, they may be simple and not nearly impressive to other games out there. But it does shine out for what it is where ever you've either played it on Steam, PS3 or 360; it does some solid visuals during certain parts of gameplay as you progress through Portal.
I would have to admit the best parts about Portal is when you have one portal high above that you go through and then firing a Portal onto the ground as you fall; Then you see yourself through the portal you came through flying across to get to a higher point to get through.
Sound is minimal, but effective and random. Hearing GLaDOS voice is amazing to hear and listen to what she has to say next. The portal gun has a cool sound to it as well when opening Portals and flying through them the credits song makes you happy when you think about Portal.
Overall: This game is short and I mean you could easily beat the game under 2 hours or more. The first 15 puzzles are simple and easy to solve but some of them will require you to think more carefully, not only that there are some challenges like Time Trail and achievements/trophies to collect. I wouldn't say that it's worth getting at full price online, if this game was released for a very small price or it's free on offer on Steam. I would recommend that it's worth download for your PC/laptop you'd be amazed how awesome Portal can be within a few short hours.