Johnny Carson

In the footage, American Astronomer Carl Sagan engages in dialogue with Johnny Carson, highlighting how children initially exhibit keen curiosity and pose clever questions but often encounter discouragement as they grow.

Don Rickles' career took off after he started making regular appearances on The Tonight Show with Johnny Carson and the Late Show with David Letterman

More than 32 years of late-night talk will pass into history next May 20, with CBS' announcement on Wednesday that David Letterman will host his final Late Show on that day.

Neil Patrick Harris is going for an awards-show trifecta and is set to host the 2015 Oscars after four hosting stints at Broadway's Tony Awards and two at TV's Primetime Emmy Awards.

David Letterman, a pillar of American late-night TV talk shows, announced on Thursday that he'll be stepping down as host of "Late Night" on CBS next year after a 22-year run.

Comedian Jay Leno said an emotional goodbye to the "Tonight Show" on Thursday with a star-studded farewell led by actor Billy Crystal, after hosting the NBC late night program for more than 20 years and handing the reins over to Jimmy Fallon.

News of Leno's departure was expected, especially since the veteran host recently began making jokes at the expense of NBC bosses in his nightly monologues.

David Letterman is set to become the longest-running late night TV show host in US history.

Talk show host David Letterman has received the highest honour at the first annual US comedy awards.

In the footage, American Astronomer Carl Sagan engages in dialogue with Johnny Carson, highlighting how children initially exhibit keen curiosity and pose clever questions but often encounter discouragement as they grow.

Don Rickles' career took off after he started making regular appearances on The Tonight Show with Johnny Carson and the Late Show with David Letterman

More than 32 years of late-night talk will pass into history next May 20, with CBS' announcement on Wednesday that David Letterman will host his final Late Show on that day.

Neil Patrick Harris is going for an awards-show trifecta and is set to host the 2015 Oscars after four hosting stints at Broadway's Tony Awards and two at TV's Primetime Emmy Awards.

David Letterman, a pillar of American late-night TV talk shows, announced on Thursday that he'll be stepping down as host of "Late Night" on CBS next year after a 22-year run.

Comedian Jay Leno said an emotional goodbye to the "Tonight Show" on Thursday with a star-studded farewell led by actor Billy Crystal, after hosting the NBC late night program for more than 20 years and handing the reins over to Jimmy Fallon.

News of Leno's departure was expected, especially since the veteran host recently began making jokes at the expense of NBC bosses in his nightly monologues.

David Letterman is set to become the longest-running late night TV show host in US history.

Talk show host David Letterman has received the highest honour at the first annual US comedy awards.