NBC got its start in 1926 as the nation's first radio network. Its parent company, the Radio Corporation of America, figured people would buy the radios it made if they had interesting things to listen to.
The network began television broadcasts in 1939 and produced TV's first star in Milton Berle in 1948. Though it faced fierce competition over the decades, NBC was formidable in the 1990s, with Thursdays declared a "must-see" night of television.
Lately, NBC has been sagging in fourth place, struggling to find a hit.
Other properties that are part of NBC Universal have struggled, too. The Universal movie studio has had notable flops such as the Judd Apatow comedy "Funny People," and theme park attendance fell in the recession.
The bright spot is in such cable channels as USA, Syfy, Bravo and CNBC. Cable TV operator Comcast has its sights on those. It wants to diversify its holdings to stave off encroaching threats from online video and rival subscription-TV providers.
In agreeing to sell a controlling stake to Comcast, General Electric is unraveling part of the legacy of former Chairman Jack Welch. In 1986 he bought RCA and NBC to help his industrial conglomerate get a reliable source of cash while overseas manufacturing competition loomed.
GE obtained the Universal entertainment business from Vivendi SA in 2004 in a deal that gave Vivendi a 20 percent stake in the combined venture, NBC Universal.
With Comcast now planning to take control, not much is expected to change immediately. NBC chief Jeff Zucker is expected to remain in charge, and there's little reason for GE to evict NBC from the GE building at 30 Rockefeller Center in midtown Manhattan.
At most the NBC comedy series "30 Rock," about a fictional version of the Peacock network, will need to satirize a different parent company -- one known for installing cable boxes rather than making microwave ovens.