The modern-day sitcom owes a lot to The Dick van Dyke Show. Its snappy wit and charm created a blueprint that's still used today by hits like Modern Family, and it was also one of the first shows to take a behind-the-scenes look at the entertainment business, a tradition continued decades later by sitcoms like 30 Rock.
Before it launched the careers of Dick Van Dick and Mary Tyler Moore, and before it was even called The Dick Van Dyke Show, it starred series creator (and legendary comedy writer/director) Carl Reiner, under the title Head of the Family. The show was the same, in essence, but the details were vastly different. The cast, the tone, the comedic rhythms, the cinematography, the set—none of it would be recognizable to anyone who's seen even a single episode of The Dick Van Dyke Show. The pilot wasn't picked up, but failure didn't stop Reiner. He re-worked it from the ground up and turned it into The Dick Van Dyke Show we know today. It just goes to show you: sometimes a failed pilot can be salvaged for something far greater than anyone working on it could have imagined.