From the Portal Wiki
Betty, also known as the Gyroscopic Liability Absolver and Disc Operating System (GLAaDOS), is a cut core-based robot that was to appear in Portal 2.
Early in Portal 2's development, while Mel was still the main playable character, with Cave Johnson serving as the main antagonist, Betty would introduce the player to each chamber in a similar manner to the one used by GLaDOS during the events of Portal. Betty was to "roll out after [Cave Johnson] had described the test," and give a disclaimer that would bar Aperture Science of any responsibility for the potential dangers encountered during testing. Betty's early model was a small Morality Core attached to a lamp from Half Life 2.
- Betty's associated acronym (GLAaDOS) was to be the only reference to the original character in Portal.
- ↑ Portal 2 - Post Mortem (GDC) on Youtube