It's not easy to be a trailblazer when so many of the trails have already been blazed, but David Letterman somehow managed to blaze one anyway.
You may think that late night television was an already-mined resource by the time Letterman, 66, came along in 1982, hosting "Late Night with David Letterman" on NBC.
It's true that TV at the witching hour was nothing new in 1982, having been first attempted some 30 years prior and being refined for 20 years by Johnny Carson when NBC gave Letterman a late night slot, following Carson's "Tonight Show."
But it turned out there was still plenty that Letterman found to do that not even the iconic Carson managed to discover.
Letterman announced today, somewhat shockingly during the taping of "The Late Show with David Letterman," that 2015 will be the year of his retirement.
"This (retirement) means Paul (bandleader Shaffer) and I can finally get married," Letterman said to a crowd that seemed to need the laugh to digest the news. But Letterman was serious---about the retirement part.
The longtime late night host said he had a phone conversation with CBS president Les Moonves not long before tonight's taping and informed Moonves that 2015 would see the end of Letterman's run on "The Late Show."
Letterman was a morning loser when NBC gave him a mulligan---a big time mulligan---and put Letterman where his milieu clearly was, in late night.
Letterman's morning show, which lasted just a few months in 1980, was a critical success of sorts (two Daytime Emmys) but a ratings disaster.
But he was back less than two years later, after midnight.
Where Letterman was able to forage---and where Carson either chose not to go or simply never thought of going---was in the mostly unexplored forest of pulling life's non-celebrities into the party.
While Carson would occasionally interview folks like an old lady who collected potato chips that looked like people and animals, Johnny's genius was in his gregarious chats with the famous and in his sketch comedy bits.
Letterman made 15-minute celebrities out of the every man with bits like "Stupid Pet Tricks" and "Stupid Human Tricks." He also made Larry "Bud" Melman---real name Calvert DeForest, a little-known actor but his day job was working for a pharmaceutical company---famous with Larry Bud's strangely humorous appearances, which many times made it seem like the joke was on Melman.
While Carson ventured into the crowd for bits like "Stump the Band," Letterman took it one step further and blended crowd games with cameos from comedic actor Chris Elliott, with hilarious results.
And while Carson had Doc Severinsen and Tommy Newsome leading the "Tonight Show" band and functioning as occasional kibitzing partners, Letterman and Shaffer formed almost a tag-team comedy duo, chatting during the first 10 minutes of each show like they hadn't spoken with each other all day.
It's no coincidence that pretty much every late night show after Letterman's employed a band with a leader who tried to be Paul Shaffer Light.
Sid Caesar and company started doing "Man on the Street" bits in the 1950s (something Carson never really did), but Letterman again turned it up a notch, beseeching the regular folks to partake in stunts and pull pranks on other unsuspecting folks---their colleagues, so to speak.
There are many other directions that Letterman took late night comedy and talk, but they are too numerous to mention here. Suffice it to say that while the genre had been discovered, Letterman took that block of clay and molded it.
"The time has come," Letterman said today in announcing his retirement a year hence.
He wasn't emotional, he wasn't melancholy. He sounded like a man comfortable in his place and with his timing.
It was as if he was saying, "My job here is done."
Which, it is.