Writers/producers/co-creators Carter Bays and Craig Thomas (II) are members of the band "The Solids," which performs the show's theme song "Hey Beautiful".
Barney and Ted meet at the urinal for the first time.
Marshall is from Minnesota.
Lily's nickname for Marshall is "Marshmallow".
From season 2, there are scenes shown before the opening credits
Ted's favorite music artist is Otis Redding.
Ted is from Ohio, just like Josh Radnor.
Ted's middle name is Evelyn.
Alyson Hannigan's character on "Buffy the Vampire Slayer" (1997), Willow Rosenberg, once mentioned that she wrote "Doogie Howser, M.D." (1989) fanfiction as a girl. Hannigan went on to star in "How I Met Your Mother" (2005) with Neil Patrick Harris, who as a boy played Doogie Howser.
Alyson Hannigan, who plays Lily, is perhaps best known prior to starring in ‘How I Met Your Mother’ for her role on "Buffy the Vampire Slayer" (1997). The creators of both of these shows -- Joss Whedon of the Buffy series and Carter Bays and Craig Thomas (II) of HIMYM -- all graduated from Wesleyan University, as well as did the characters Lily, Ted, and Marshall on HIMYM.
