Johnny Carson, an icon of late-night U.S. television, has died at the age of 79.  NBC, Mr. Carson's network throughout his Tonight Show  run, says Mr. Carson died Sunday from complications of emphysema.

Carson hosted The Tonight Show  for a record 30 years. Millions of Americans tuned in each night before bed to enjoy Carson's quick wit, smooth interviewing style, and often hilarious opening monologue.

Topics of Carson's humor included current events, politicians, and Mr. Carson's own love life -- he was married four times.

His retirement in 1992 became a national event that drew some 50 million television viewers.

Carson gave many top comedians their first national TV exposure, including David Letterman, Jerry Seinfeld, and Carson's successor as host, Jay Leno.

It was revealed just a few days ago that Carson was still sending in jokes to Mr. Letterman, who has his own late-night comedy show today.

Some information provided by AP.