It’s a reminder of how vital late-night TV used to be. A 16-year-old interaction with a totally different man is still a hotter topic than anything the new guys can drum up.

Here now is our Top 10 list of how David Letterman changed late-night TV. 10. Before Letterman, late night was synonymous with one person: Johnny Carson.

The end of “The Late Show” was every bit as writ-in-stone as any of those predictable downfalls. And it’s not only Colbert. The Grim Reaper is coming for all of late-night TV. Those ...