In Sharon's dream world of Harry Barker, a sprite is a form of "digital creature"—an artificial intelligence given form via a virtual reality avatar—whose primary purpose is to act as a servant or assistant. There are multiple classifications of sprites with varying degrees of functionality, intelligence, and independence. However, all sprites are bound by their code to serve the hacker they were programmed for. Failure to obey their master could result in a reboot (which erases the collected memory of the sprite and thus any evolved personality) or complete erasure. However, it is said that a hacker can free a sprite under his or her command by giving it its own user account, signifying that it can run independently of its owner.
The only sprite we've encountered so far is Noddy, a network sprite owned by Luser Mouso. During "Harry Barker and the Chatroom of Enigmas", Mouso surreptitiously attempted to reboot the Chat Room of Enigmas by planting an optical disc containing a data ghost of a younger version of Gnawthrylilees on a student at Hollerith's, which ended up being Jenny Measly. Aware of Mouso's plan, Noddy attempted to "protect" Harry Barker by preventing him from returning to Hollerith's. After Harry found and survived the Chat Room, he presented the broken disc to Tim Dumpingcore. Mouso shortly arrived with Noddy in tow. While Dumpingcore and Mouso verbally sparred over the disc's origin, Harry learned of Noddy's servitude to Mouso. Harry then tricked Mouso into giving Harry's ID access card to Noddy, symbolically giving the sprite a user account and effectively freeing him. Noddy responded by protecting Harry when Mouso attempted to physically attack him.
Sprites are the analog of house-elves from Harry Potter. They are loosely derived from sprites in computer graphics, a form of two-dimensional bitmap that is integrated into a larger scene. It is also tangentially derived from the TV series ReBoot, where most of the show's characters living in its computerized world are referred to as "sprites".