What is portal's summary?

Answer 1

This is off the top of my head so I will undoubtedly miss some details.

The first one is about your character, a woman named Chell, participating in tests at the Aperture Science Facility while a witty AI with a female voice named GLaDOS comments on your progress. After completing the final test, GLaDOS tells Chell that she is going to be rewarded, but it turns out that she is going to be thrown into a furnace. She escapes the furnace and begins running around the innards of the facility, seeing all the behind-the-scenes mechanisms that go into making the tests. After running through all that, Chell makes it to GLaDOS' chamber. GLaDOS informs Chell that she, that is GLaDOS, had previously killed everyone in the facility by releasing a "deadly neurotoxin." She then releases the same neurotoxin in her chamber in an attempt to kill Chell. As one would expect, Chell defeats GLaDOS, and the game ends with a bit of a cliffhanger, as the fate of Chell is not really specified, but it can be assumed that she dies, lying on somewhere above the facility on the surface.

The second one starts off with Chell waking up from stasis after an unspecified, but presumably VERY long, amount of time. An AI named Wheatley finds you, and informs you that the facility's reactor is unstable and will self-destruct. Chell travels through the facility with Wheatley until they come across GLaDOS' chamber where she lies deactivated. While trying to secure escape, Wheatley reactivates GLaDOS. She remembers that Chell killed her, and forces her to participate in more tests.

After a bit of testing, Wheatley makes an appearance and helps Chell escape the test chambers. He has a plan to stop GLaDOS by sabotaging the production of her turrets and neurotoxin. This allows Chell to confront with GLaDOS without dying. Chell activates the override that ejects GLaDOS' personality from her "body." Wheatley tells Chell to insert him into GLaDOS' body so that he can gain control of the facility and escape. Upon doing this, he realizes how much power he has and decides to keep Chell from escaping. He throws Chell and GLaDOS down a shaft. While falling down the shaft, GLaDOS remembers that Wheatley was an AI module designed to hinder her by being an idiot. She actually says that he was an idiot designed by the scientific community's greatest minds so he's pretty stupid...and now he controls the facility.

At the bottom of the shaft, Chell and GLaDOS find themselves in the oldest part of the facility, made back in the 60s. This part of the facility contains backstory on Aperture and its president Cave Johnson as recordings of him are played throughout the tests. GLaDOS, it is revealed is lovingly based on Cave's secretary. The two eventually make it back to the modern part of the facility where everything is falling apart due to Wheatley's incompetence. This includes the reactors as he has simply turned off the alarms warning of their imminent meltdown. The two run through myriad tests and make it to Wheatley. A battle ensues ending in Wheatley's defeat. I'm not going to spoil how, as it's utterly badass and needs to be experienced firsthand, or watched on YouTube.

So GLaDOS is reinstalled into her body, she returns to her old, evil self and stabilizes the reactors. She still holds a grudge against Chell for killing her in the first game, but decides that she doesn't want revenge anymore. Instead, she wants Chell to "just go," and summons an elevator for Chell to leave the facility and return to the surface.

That's pretty much it.