Can you believe it's been 19 years since we first boarded the Hogwarts Express with Harry and his friends?
In 1997 - the year Harry Potter and the Philosopher's Stone was released - Hanson's song 'MMMBop' was top of the charts, the other Clinton was President and One Direction's Harry Styles was too little to be breaking hearts.
Reading has also changed a lot since then.
Children's books were much shorter - the American Library Association says since the first Potter book, children's novels have got 60 percent longer.
Twitter and Facebook didn't exist yet, so the only risk of spoilers was from some know-it-all in the playground.
When Harry Potter and the Deathly Hallows - the last book in the series - came out in 2007, the Kindle e-reader hadn't yet been released, so long queues and waiting lists at bookshops were the norm.
The Harry Potter empire is now said to be worth something like $21 billion, thanks to movies, merchandise and theme parks.
All this from a little book whose first print run was only 500 copies because back in 1997, people thought kids had stopped reading.