|First game||Portal (2007)|
|Voiced by||Ellen McLain|
GLaDOS (Genetic Lifeform and Disk Operating System) is a fictional artificial intelligent computer system found in the Valve Software video game Portal, voiced by Ellen McLain. She initially appears as a voice to guide and aid Chell, the player's character, through the game's chambers, but over time, her words and actions become stranger, and she makes multiple attempts to kill Chell. After a face-to-face confrontation with GLaDOS, Chell destroys her and escapes. GLaDOS was universally praised for her contributions to the quality of Portals writing, winning multiple awards for best new character from GameSpy, GamePro, and X-Play.
At the end of "Portal," Ellen McLain performs again as GLaDOS in a song called "Still Alive" by Jonathan Coulton, which has become an internet hit, receiving praise from multiple outlets for the quality of its writing. It has been featured in multiple installments of the Rock Band series as free downloadable content. It is also available for purchase as a part of the Orange Box original soundtrack on iTunes.