GIR is a malfunctioning "SIR" unit, essentially a robotic henchman for Zim. GIR possesses all of the strengths and weaknesses of being a mechanical being, in addition to "superior geographic abilities" that were given to him by Zim. In his head there are an array of various weapons, but he rarely uses them. There is also a great deal of empty space that he uses to store things, like a giant pile of rubber piggies, a puppy, or even a beehive. He also has X-ray vision, the ability to shoot lasers from his eyes, and jets in his feet.
Every so often, GIR will display brief instances of complete functionality, usually when Zim issues an order to him. This is known as "Duty Mode", usually signified by GIR's lights suddenly turning red and his overall personality become more dutiful and robotic. These random bouts never last for long, though, and after a few seconds, GIR is right back to his gleeful, hyperactive self