famous initials

MAN - Maschinenfabrik Augsburg Nürnberg.  Here an advertisement for an AC electric railcar from the 1930s.

BBC - yes British Broadcasting Corporation, but also Brown, Boveri and Company, in Mannheim: an advert for an electric railcar, likewise 1930s.

Both companies still operate, the first's vehicles are the better known internationally.  BBC merged with Swedish ASEA in 1988 to form АВВ (Asea Brown Boveri Ltd).