With the Harry Potter story drawing to a close, it will mean the end of an era for millions of readers who have followed the young wizard's adventures.
Here, six fans explain how Harry Potter has become part of their lives.
ROBYN WALKER, RUNCORN, CHESHIRE
I was seven when the first book was published, but I didn't start to read them until the third book was out.
Fans can start reading the final Harry Potter book from Saturday
I remember on Boxing Day 2000, the whole book was read on the radio by Stephen Fry and I got up early and listened to the whole thing. I can honestly say, that was the only year our whole family was silent on Boxing Day! After that my mum and dad bought me the other two and we waited in line for the fourth one.
We will be going to our local Asda for the last book as that's where we went for the sixth. And after that, I'm locking myself in the cupboard under the stairs with a week's supply of milk and cookies until I finish it! I don't want to hear what happens before I finish reading it for myself!
ABI C, BATH
I started reading Harry Potter when I was nine, and I'm 15 now, so six years of my life have been 'wasted', as one may say, on Harry Potter. I have waited outside my local Waterstone's for the last three books (Order of the Phoenix, Half Blood Prince and, tonight, Deathly Hallows), and am really looking forward to it.
A few people who got the book early posted on my friend's internet blog, telling her the plot. She was devastated. Luckily, they were in image format, so she only saw the top of each image and deleted them before they loaded.
I would be horrified if someone told me the plot. I've spent so long speculating, finding out before I'm supposed to would be horrendous.
ALEXANDRA, SYDNEY, AUSTRALIA
I started reading these books when I was 11. I am now 18. I definitely will be waiting outside the bookstore for this book, as it has contributed so much to my life as I went through high school and now uni.
It is so exciting that there is another book coming out - presently, I am cramming in the Half Blood Prince (200 pages and 14hrs left to go). I have so say, though, it is really sad to think that this is the last adventure I will go on with Harry, Hermione and Ron.
The Harry Potter series are what started me reading and have been a constant source of inspiration and amusement for the past seven years of my life - and I will miss them dearly.
HARRIETTE TANNER, SELSTED, KENT
I've grown up with these books, starting to read them at the age of six and would be absolutely fuming if someone spoilt this last adventure for me. My whole family loves the Harry Potter books with a passion and we have a strict rule whereby until everyone is finished there is no discussing the book at all!
The new book is being released in children's (left) and adult editions
I will be in Canterbury tonight at a street party to welcome this final instalment in a classic series. My only regret is that this is the end, but I thank JK for giving us the opportunity to read these books.
SOKUNPANHA YOU, PHNOM PENH, CAMBODIA
I grew up in a country where English wasn't even the second language. The world of Harry Potter was introduced to me rather late when I was in high school. From the first page, I haven't really grown too old for what are otherwise supposed to be children's books.
For me, Harry Potter was the starting point of not just a hobby, but a passion. By the time I read the first Potter book, I'd already been an avid reader, but I did most of the reading in my native Khmer language.
Harry Potter books were what got me into reading in English. I have since then ventured to enjoy both classic and contemporary English literature such as the work of Dickens, Austen, the Bronte sisters, Hugo and many more.
I can now hardly go through a day without doing some reading. And all this started by a bespectacled boy living in a broom shed under the stairs.
MARIA L, MANAGUA, NICARAGUA
I was five or six when I started following Harry Potter and his magical troupe. I actually got the books from my mom, who'd been reading them first, and I was the one responsible for spreading the enchantment to many of my friends, most of whom became huge fans in time.
July 21st, marks an important transition - as the Hogwarts gang close the chapter on childhood and move forward to an unknown future, so many of his fans (myself included) begin to drift towards much the same thing.