It's 20 years since the publication of Harry Potter and the Philosopher's Stone - the first Harry Potter novel by JK Rowling that began one of the most successful book and film franchises of the past two decades.
To mark the occasion fans have taken to social media to share their tributes.
More than 60,000 tweets were generated in the first 24 hours using the hashtag #HarryPotter20 which is trending worldwide.
Tweets have been building over the past week as many social media users - particularly from the millennial generation who grew up with the coming of age tale - have been sharing why they think the books are more than just good stories.
Some people shared quotes from the book, and images and memes from the films to mark the anniversary.
One Twitter user uploaded a gif of an emotional Ron Weasley with the post: "There's nothing that makes you feel old quite like Harry Potter being 20 #HarryPotter20".
Others thanked the author JK Rowling whose manuscript of the first book was rejected a number of times before being published in 1997 with a print run of just 500 copies.
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Social media features
The social media networks aware of the magical allure of the Harry Potter phenomenon have launched new features for their users.
Twitter has a new emoji of Harry Potter's famous round glasses and lightning bolt scar. Facebook has rolled out an Easter egg - a kind of special effect treat within a piece of software.
If you post or comment on "Harry Potter" or the name of any of the Hogwart School houses, the word is shown in the house colour. Also, an animated wand appears when users click on the names.
One user posted: "This is the best thing Facebook has ever done. You click on Harry Potter and a wand, sparks and lightning all appear! It's magic!"
Snapchat have also reintroduced their Harry Potter filter where users can post pictures of themselves as the boy wizard.
Hannah Owens from London told the BBC: "I'm of the generation that grew up with Harry Potter and queued for hours for the new book at midnight. I loved it as a child and nothing has changed now I'm a grown up!"
By the BBC's UGC and Social News team
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