MegaMan.EXE, known as in Japan, is the NetNavi (short for Internet Navigator) operated by Lan Hikari. He was created by the scientist Yuichiro Hikari, Lan's father. MegaMan.EXE is quite powerful, and along with his operator Lan, is a very skilled virus buster. He is also Lan's twin brother, Hub Hikari (Saito in Japan) who died at birth, because of a rare heart condition known as HBD (unknown meaning). Dr. Hikari then used his data to revive him as a NetNavi, MegaMan.EXE.