In 20XX...
... the rapid advance of internet technology has created the "network age." Everyone now caries a portable exploration device called "PET." This personal terminal is an advanced personal digital assistant. Using it, you can make phone calls, send and receive emails, keep a calender, store data, shop online and check news from around the world. PET is so convenient and helpful that it has become essential for everyday life!
Every PET uses a peronality simulation program called Net Navi(gator.) By customizing your PET's Navi program, you can give your Net Navi a unique personality - and even talk to it!
But as the network world expands, network crime is raging. Hacking and computor virus epidemics have become major issues. At the top of the criminal list is a mysterious organization called "WWW" (World Three), a group of incorrigible computor hooligans.
To protect their PETs, people have begun installing Battle Chips - special chips encoded with battle programs. When you insert a Battle Chip, you can arm yur PET to fight off viuses and hackers. This is called "Virus Busting" and has become so important that it is now taught in schools.
Lan is a 5th grade student. His Net Navi (and best friend) is Mega Man.EXE. Lan and Mega Man.EXE are both extremely skilled computor operators.
In the world of virus busting, Lan and Mega Man.EXE are aboutto meet their match...