Mater's Computer is a computer that is utilized by the British Intelligence. While the computer is highly intelligent, it will take all the commands it receives literally, which will sometimes result in an effect that is different from the desired one. While it is simply a piece of technology, its voice resembles that of a female.
In Cars 2, while Mater sneaks into the Lemons' secret gathering in Porto Corsa, Italy while dressed as Ivan, he is given a computer by Finn McMissile and Holley Shiftwell, which will assist him with his task. During the meeting, it is revealed that the Lemons intend to use their electromagnetic pulse camera on the World Grand Prix contestant Lightning McQueen, who is still using Allinol, a fuel substance that, when hit with an electromagnetic pulse, will cause a small explosion in the target's fuel tank and subsequently damages their engine.
This revelation surprises Mater, who jolts forward and accidentally hits part of his disguise on the ceiling, causing his true appearance to be seen. The Lemons attempt to capture him, but Mater, who exclaims, "Oh, shoot!", accidentally uses his computer to shoot machine guns at them. When Mater tries to correct the computer, it activates his parachute, which he uses to safely glide to the ground to warn Lightning.
Later, while in London, Mater again uses his computer to use his parachute, which he and Lightning use to reach the Queen in order to expose Miles Axlerod and the rest of the Lemons' scheme.
Cars 2: The Video Game
In Cars 2: The Video Game, Mater's computer is used to provide instructions to the player prior to the start of an event. Additionally, it is heard upon the activation of certain items, such as the Satellite Quake.