Story

The Portal games are story driven games, as such the scenario takes an important place in the gaming experience.

In the games you play Chell, a young women stuck in an Aperture Science complex forced by the Artificial Intelligence GLaDOS to solve tests in specialy designed chambers using for solving them the Handheld Portal Device.

Portal
The game has two distinct acts, the test chambers and the escape.

Act 1: The test chambers
The game begins with the player awakening in a Relaxation Vault where they are briefed by an unseen voice, GLaDOS, before being released through a portal. The player is introduced to the testing process and mechanics cumlinating in the procurement of the Handheld Portal Gun. As Chell makes her way through test chambers it becomes clear Motivating Chell with the promise of Cake at the end of the testing, Chell is put through tests of increasing complexity.

Portal: Still Alive
Portal: Still Alive is a Xbox 360 Live Arcade port of Portal, containing additional content in the form of new advanced chambers, inspired by Portal: The Flash version.

Portal 2
Portal 2 was realeased simultaneously on PC & Mac, Xbox 360 and PS3 so the story is the same for each platforme.

Single Player
The narration in Portal 2 is completely differente, it introduces a clear separation in chapters (similar to the chapter in Half-Life), each chapter making the story progress. You still play Chell, equipped with the Portal gun, but the testing isn't a significative part of the story, not as much as in the original game, the story has more depth than simply testing.