How I Met Your Mother

How I Met Your Mother was inspired by Carter Bays and Craig Thomas' idea to "write about our friends and the stupid stuff we did in New York", where they previously worked as writers for Late Show with David Letterman, among others.

Ted is based loosely on Bays, and Marshall and Lily are based loosely on Thomas and his wife.

Thomas' wife Rebecca was initially reluctant to have a character based on her but agreed if they could get Alyson Hannigan to play her.

Josh Radnor and Jason Segel, who were cast as Ted and Marshall, respectively, were not well known, although Segel had been a cast member on the short-lived Freaks and Geeks and a recurring guest star on Judd Apatow's follow-up show, Undeclared.

The role of Barney was initially envisioned as a "John Belushi-type character" before Neil Patrick Harris won the role after being invited to an audition by the show's casting director Megan Branman.

Pamela Fryman invited Bob Saget to be the voice-over narrator, Future Ted, explaining to him that the show would be like The Wonder Years but "kind of into the future".