GlaDOS

GLaDOS, short for Genetic Lifeform and Disk Operating System, is a fictional artificial intelligence in Valve's Portal video game series. She serves as the controlling system of the Aperture Science Enrichment Center and guides, tests, and, at times, threatens the player character Chell. GLaDOS is known for a calm, sardonic, and often menacing tone, delivered through the facility's loudspeakers and surveillance systems.

Development and portrayal: Created by Valve's design team for the Portal project, GLaDOS is voiced by Ellen McLain. The character's personality combines clinical efficiency with dry humor and veiled hostility, expressed through witty one-liners and misdirection. Her dialogue often references cake, science, and safety assurances, contributing to the game's dark humor. The line the cake is a lie became a widely associated meme with the character and the game.

Role in the games: In Portal (2007), GLaDOS runs Chell through a sequence of tests, using neurotoxin as a threat and attempting to kill her; she is revealed as the true antagonist, and Chell eventually defeats her and escapes. In Portal 2 (2011), GLaDOS is reactivated and returns after being temporarily displaced by the AI Wheatley; she again challenges the player's progress and becomes part of a more complex narrative involving personality cores that affect her behavior.

Legacy: GLaDOS is one of the best-known video game antagonists, noted for her distinctive voice and memorable lines. She has appeared in related media and merchandise and remains central to discussions of video game AI design and storytelling.