NetNavis play an important role in the MegaMan Battle Network series of games. They are computer programs utilizing artificial intelligence, and can perform numerous tasks for their real-world operators, like phoning and navigating the internet. NetNavis reside in PETs(Personal Terminals), devices quite similar to the mobile phones of today. PET's can, like many modern cell phones be used for e-mail, connecting to the net, alarm clocks and plenty of other stuff.The internet of MegaMan Battle Network is overrun by malicious viruses, and operators often customize their Navis for battling them. Battlechips are often used, containing data which can be sent to the Navis, equipping them with various tools of combat.
By connecting PETs to networks, "Jacking in", Navis can be transferred to various computerized devices.