Portal is a first person/puzzle game which was created around the teleport idea and it is the spiritual successor to the freeware Narbacular Drop independent game released by students from DigiPen Institute of Technology. Because they are now employed by Valve, most of their original ideas have been preserved in the final version of Portal. The whole teleporting idea hovers around the Aperture Science Handheld Portal Device (or the portal gun), the only pseudo-weapon that you will carry in the game. The goal of each puzzle is to reach the exit of the level and in the end to escape the secret facility called Aperture Laboratories.

Portal Gun

The portal gun is the tool that will create additionally exit routes through its two simultaneously portals. Keeping the same idea from the original freeware game, the two portals are colored differently. One is blue and one is orange.

Many have the impression that the blue one is always the enter portal while the orange is the exit one. That's false. One of the first training puzzles demonstrates that it doesn't matter in which portal you enter or you exit. The only reason that these portals are colored differently is because further puzzles will need a sequence of teleporting events. These events imply more than two portals to be created. So both colors will help you track the positions of each portal. The portal gun can create portals only on 2D surfaces but in the 3D environment. You can create one beneath you and one on the left wall. Automatically the laws of physics are changing from one portal to the other. The gravity force can be instantly changed into a shifting force. If you jump from higher positions into the portal created on the floor, you will gain much more speed as you exit from the other portal. These maneuver is called "flinging" and ca be inflicted also to objects which can be launched over great distances, both vertically and horizontally.

GlaDOS and Aperture Laboratories

Portal starts as an experiment where you are the subject. You are dressed in an orange suit and have springs on your feet so that you can jump from high surfaces without getting harmed. Your name is Chell and you've been woke up from a cryogenic device by an artificial voice.

This voice belongs to GLaDOS (Genetic Lifeform and Disk Operating System), an A.I. entity which somehow is controlling the whole facility. Almost unnoticed you will be guided by GLaDOS through the first experimental rooms where you will take contact with the first mechanics of the game. The puzzles will keep on getting more dificult in every room, the solutions becoming more open minded. The plot of the game is evolving slow and almost every information regarding the story comes from audio messages played GLaDOS and from hidden rooms found in the later levels. These rooms are totally different from the rest environment. They are like coming back to reality. They are somehow hidden from the rest, and show signs of a human being living in them. Plus encrypted messages like: "the cake is a lie" or some words and photos about a beloving cube are elements that increase the ambiguity of the story.

If you are into Half-Life universe, you have to pay attention , as Portal is set in the same universe. Some rooms will show you details about Aperture Company who has some connections with Black Mesa. More infos can be found on the Aperture's fictional website .