*NOTE: In Japan, Megaman is Rockman and Protoman is Blues. This line of naming runs along musical themes: Blues, Rock and Roll. Forte/Bass joins the series later on. Support units Rush, Tango, Beat, and Gospel/Treble also fit this name basis.
Mega Man has two siblings. Protoman, his darker sibling, is lonely, and mysterious, and sometimes is framed by Wily as an evil robot. His other sibling is Roll, but for some odd reason, the creators of Capcom decided to make Roll as Mega Man's love interest which is really disturbing since they are siblings...but who cares, robots can do anything.
Mega Man has 8 games in the original series, MM1-6 on the NES, MM7 on the SNES, and MM8 on the PS1. Recently, all 8 games plus 2 Mega Man arcade games were released in the Mega Man Anniversary Collection.
Mega Man also has an anime that aired long time ago.
It's also important to note that the MegaMan series started in Japan under the name "RockMan". It was later dubbed into "MegaMan" When it was translated, and brought to other nations, especially the United States.
2. Fight, MegaMan... for everlasting peace!