Today marks 20 years since the first Harry Potter book was published, and several things are happening today to mark the occasion.

First off, Twitter Queen J.K. Rowling shared a special message to commemorate the anniversary:

Meanwhile, Facebook has rolled out a feature to most users which adds House colors and effects to the words Gryffindor, Slytherin, Hufflepuff, Ravenclaw, and Harry Potter. Tapping any one of those words in status updates will trigger special effects. And while most people seem to have received the feature, many people — this writer included — don’t have it. Check out a demo:

Finally, the new cast of Harry Potter and the Cursed Child are celebrating the anniversary by flipping through the new House Edition Harry Potter books. This week the play is giving away copies of the book to lucky attendees.