WALL•E was designed to be an environmentally-friendly garbage-processing robot. As such, he possesses many interesting devices to help him fulfill his directive. Because WALL•E has been alone for 700 years, he has developed a “glitch”: sentience and a personality.
He has become very curious and he keeps anything interesting he can find. Even though he still obediently follows his directive, WALL•E can get distracted, collecting the trash rather than compacting it. His most prized possession.