How to unlock Harry Potter Easter eggs on social media
- Published
The films launched the careers of Emma Watson, Daniel Radcliffe and Rupert Grint
Facebook has launched an Easter egg which fills users' screens with sparks from a wand to mark the 20th anniversary of the release of Harry Potter and the Philosopher's Stone.
The first hardback run of JK Rowling's series, on 26 June 1997, was just 500 copies.
It's now sold more than 450 million books around the world.
Twitter has got on board too by making a special emoji of Harry's trademark glasses.
Here's how you get them.
We couldn't resist giving it a go
On Facebook all you have to do is type "Harry Potter" into a status or comment, followed by the name of one of Hogwarts' houses.
In case you've forgotten - you've got four to choose from: Gryffindor, Hufflepuff, Ravenclaw and Slytherin.
The text will then change colour and when you click on it a wand will appear and shoot sparks across the screen.
What JK Rowling said about first Harry Potter book in 1997
On Twitter, an emoji appears when people type the hashtag #HarryPotter20.
Fans have been using it to share their memories of the series.
Saytanim uploaded a photo of the birthday cake Hagrid gives to Harry in the first film., external
Janvi said: "Once a Potterhead, always a Potterhead"., external
Of course, there aren't just JK Rowling's books to talk about. The series also spawned one of the most successful film franchises ever.
The final instalment, Harry Potter and the Deathly Hallows Part 2, is the eighth-highest grossing movie of all time.
The franchise continued in 2016, with the spin-off Fantastic Beasts and Where to Find Them.
JK Rowling says she has plans for five more Fantastic Beasts films.
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