* AdaptationDisplacement: The film version has pretty much overshadowed the original stage play.
* CrowningMusicOfAwesome: "I Could Have Danced All Night" has gone down in the record books as one of the most beloved soprano solos in the history of musical theatre -- and with ''very'' good reason.
* DawsonCasting: Audrey Hepburn was in her mid-thirties when she played the 21-year-old Eliza in the film adaptation.
** The life of an apparently quite poor flower girl in those days probably would have aged the character of Eliza beyond her years; in this case, DawsonCasting may have been justified.
*** Furthermore, Audrey Hepburn always looked younger than she actually was.
* EarWorm: [[http://youtu.be/7Ezy50aY6Bg I COULD HAVE DAAAAANNCCEEEED ALL NIIIIIGGHHT! I COULD HAVE DAAAAAANNCCEEED ALL NIIIIIIGHT! AND STIIIILLL HAVE BEEEEEEGGED FOR MOOOOOORRRREE!"]]
* FanPreferredCouple: Eliza and Henry, to Shaw's consternation.
* GeniusBonus: In the film, near the beginning we get a glimpse of Henry Higgins' notebook, which he's using to transcribe people's accents. It's unreadable... unless you understand [[http://en.wikipedia.org/wiki/Shavian the Shavian alphabet]], whose creation was funded by George Bernard Shaw.
* HoYay: Higgins and Pickering have quite a bit, particularly in "A Hymn to Him", where Higgins straight up asks "Why can't a woman be more like a man?".
* MemeticMutation: "The rain in Spain falls mainly on the plain."
** "I've grown accustomed to her face."
** When it was first made, Eliza came across as much more unacceptably uncouth to theatre-goers, and therefore just as bad as Henry, whereas it's getting more and more common to see Henry as a misogynistic, snobbish villain unfairly putting Eliza down. Basically, they're each supposed to be a JerkWithAHeartOfGold, but current values don't look favorably on characters like Higgins.
** Freddy's love-sickness and patient wait is stalking in today's terms, and while it would have been seen as romantic by all parties at the time, easily disturbs people nowadays.