This article contains spoilers. Read at your own risk!
It might spoil your gaming experience when first playing the related games.
The title of this article is conjectural.
Although this article is based on official information, the actual name of this subject is pure conjecture.
This article is about the robotic arms. For the configurable walls, see Aperture Science Panel.
Throughout the Enrichment Center, these arms carry out a wide range of functions, and are commonly configured to work with the Aperture Science Panels.
The Multitasking Arms are a retconned structural element introduced in Portal 2, ultimately replacing the thick steel pistons that had originally wielded the panels in Portal. The Multitasking Arms are configured on par with the Panels by GLaDOS. They are deployed by pistons before they are put into their grids, where they can then build or reconfigure Test Chambers. Once the arms are attached to their grid, the pistons are free to be detached from the arms. The Multitasking Arms not only form the testing areas, as they are the structures used to configure even the offices of the Enrichment Center.
The arms are also proven to have been used for different tasks when Chell finds Wheatley, one of the many Personality Cores to have been traveling on their ceiling-constricted Management Rails - attached to a Multitasking Arm. The arms would weld Cores to its magnetic receiving end until the Core eventually chooses a proper location to be detached from the arm. Strangely, the arm had only been used in this manner once, despite that Wheatley did not use it to continue traveling on his Management Rail later on.
In the Turret Manufacturing department, one of GLaDOS' cameras was attached to a Multitasking Arm. This ceiling-constricted mobile camera was used in scanning the quality of a Sentry Turret when compared to a template Turret. This method of holding cameras was then reused at the beginning of the cooperative campaign, in the Calibration Course. However in co-op, it utilizes the Portal 2 version of the security cameras instead, unlike the Turret Manufacturing camera which uses the Portal equivalent.
The arms are of further importance in the role of Central Core Transfer procedures, and are located beneath the Central AI Chamber. Under protocols, GLaDOS must prepare a Core Transfer hatch beneath her design of the chamber. This hatch was later used by Wheatley with the help of Chell to overthrow GLaDOS from her control over the Enrichment Center. Here, the arms are present in a much larger and partially painted in red, as they perform a painful procedure on GLaDOS in order for her to be completely detached from the Central AI body. Then, the arms rig Wheatley into an input port on the Central AI body, where he is given the rank of managing the Enrichment Center.
In some cases, a Multitasking Arm would be presented with hints on a possible sentience. In one of the Testing Tracks managed by GLaDOS, an arm can be seen repeatedly rotating a Weighted Storage Cube above a panel, almost displaying a sign of teasing if not impatience. In another instance, several wall panels on arms can be seen slamming or pulling into other wall sections, appearing angry when doing so. While Chell rides a metal panel in Turret manufacturing, Multitasking arms carrying other panels move their teal circles up and down a bit as they pass, as if looking directly at her. Later when Chell falls into a booby trap by GLaDOS near the Central AI Chamber, the panels surrounding the area are lifted up for the arms to peek at her. This repeats when Wheatley takes over the Central AI body as the arms stare into the elevator carrying Chell, and shortly in the ending monologue as GLaDOS has finally come into touch with her humanity. The arms are then lowered and put into positions once GLaDOS claims to have deleted Caroline from her programming.