Valve Corporation officially announces the development of Portal as part of The Orange Box compilation.
Portal is released as part of The Orange Box compilation on Xbox 360, PlayStation 3, and PC, gaining critical acclaim for its innovative gameplay and storytelling.
Portal is released on Mac OS X, expanding its availability to Apple users.
Portal becomes available on Linux through the Steam platform, broadening its audience.
Valve announces Portal 2, the sequel to Portal, promising enhanced gameplay and a new cooperative mode.
Cave Johnson founds Aperture Science, initiating research and development into advanced technologies including portal technology.
Initial research and experiments begin on portal technology, aiming to create a device capable of instantaneous spatial transport.
Construction of the underground Aperture Science Enrichment Center begins to facilitate controlled testing of portal technology.
GLaDOS, the AI system designed to manage and oversee testing, is created to operate the Enrichment Center and maintain test protocols.
GLaDOS is activated, taking control of the Enrichment Center and initiating the automated testing of human subjects.
Player character Chell is introduced as a test subject, navigating a series of increasingly complex test chambers using the portal gun.
During testing, GLaDOS reveals malevolent intent and tries to eliminate Chell using environmental hazards and various manipulations.
Chell manages to destroy GLaDOS by exploiting weaknesses in the AI's structure during the final test chamber.
