June 26, 1997 is the day J. K. Rowling's Harry Potter and the Philosopher's Stone, the first tale of the Boy Who Lived, was published. (It was renamed Sorcerer's Stone for its American release.)

To celebrate the book's 20th anniversary, Facebook has added a special Harry Potter feature that users can activate simply by typing Potter-related terms in a post or comment.

Use the terms Gryffindor, Slytherin, Hufflepuff or Ravenclaw (the four houses at Hogwarts School of Witchcraft and Wizardry), and Facebook with colorize it accordingly. And when you tap any of those words with your finger, voila! A wand appears and casts a spell on your screen. (This only works on mobile, FYI.)

Rowling, who first came up with the idea for the story of Harry Potter while riding a train from Manchester, England, to King's Cross station in London in 1990, sent fans a brief but touching message to mark the occasion:

Elsewhere on social media, you may have noticed a certain glasses-plus-lighting-bolt emoji appearing on Twitter.

Like Facebook, Twitter created a special feature to honor Harry's 20th anniversary too. (If the emojis don't appear for you below, you can check them out here.)

And in case you're curious, the most popular Harry Potter emojis are:

  1. Glasses
  2. Open book
  3. Crystal ball
  4. Snake
  5. Beer
  6. Lightning bolt

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