-J.K. (Joanna Kathleen) Rowling thought up Harry Potter while on a train from Manchester to King's Crossing, but she had to wait to write her ideas down because she didn't have a working pen!
-She made up names for the 4 Hogwarts houses on the back of an airplane sick bag.
-Book publishers used Joanna's initials for the book covers because they thought boy's wouldn't want a book written by a woman.
-When trying to sell the first book, Rowling was so poor she had to type two copies of the manuscript because she couldn't afford to photocopy the original. She also wrote most of the first book in Nicholson's, an Edinburgh café?, because her apartment was too cold! Now, thanks to Harry, J.K. is the third richest woman in Britain!
-"Goblet of Fire" was originally published with a mistake saying that the ghost of James Potter emerged from Voldermort's wand before Lily Potter, when it should've been the other way around. This was corrected in later versions of the book. (I have the first one hehe).
-Hermione's character is based on JKR.
-Ron wasn't intentionally based on anyone, but he turned out like JKR's friend Sean.
-If you read the inscription on the mirror of Erised backwards it says "I show not your face but your hearts desire".
-Gilderoy Lockhart's favorite color is lilac.
-Argus Filch, the failed wizard who lives to catch Hogwarts students doing things they shouldn't be doing, is named after the watchman in Greek mythology who had eyes all over his body.
-Dumbledore is 150, McGonagall is 70, Snape is 35 or 36.