* AdaptationDisplacement: The film version has pretty much overshadowed the original stage play.
* 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.
* 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".
* MemeticMutation: "The rain in Spain falls mainly on the plain."
** "I've grown accustomed to her face."
* TheyJustDidntCare: Instead of comissioning a new restoration for the 2011 Blu-Ray, CBS just upscaled a 1994 restored version to 1080p. However, the 50th anniversary Blu-Ray from 2014 boasts a newer, 4k restoration.
** In its original release, 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 villain putting Eliza unfairly 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 would have been seen as romantic by all parties at the time, easily disturbs people nowadays.