100 years ago today, children's author Roald Dahl was born in Cardiff.
The splendiferous writer is being celebrated at events around the world today, including an Enormous Crocodile bench being unveiled in Cardiff Bay.
More than 200 million copies of Dahl's books have been sold around the world and translated into 59 languages.
Lots of schools are celebrating his birthday by dressing up as their favourite villains and heroes.
So we want to know what your favourite Roald Dahl book is and if you are doing anything at school today to celebrate?
My favourite book from Roald Dahl is Matilda because it's very interesting to see how she copes with her parents. I hope she's having a nice life with Miss Honey.
Emilie, 11, London
Charlie and the Chocolate Factory
Rebeccca, 16, Bridgend
I like boy tales of childhood, going sola, the BFG, and james.
Beth, 16, Northampton
My favourite book is the BFG because I think giants are awesome! Also because it is a great adventure that I can't get enough of. We also did Roald Dahl day at school on the 13th of September celebrating 100 years since he was born in Wales. I went as the BFG!
Thomas, 9, Daisy Hill
My favourite is Matilda because you can be who you want to be no matter what.
Charlotte, 10, Sutton
My favourite book is James and the Giant Peach.
Abigail, 8, Feltham
My favourite book is Matilda.
Hope, 16, Perth
My favourite Roald Dahl book is Danny the champion of the world because it's very exciting and the way he wrote it makes you want to read on.
Jake, 9, Motherwell
My favourite book is the enormous crocodile.
Matthew, 6, Motherwell
My favourite is charlie and the chocolate factory, it is my class theme as well.
Seren, 8, Gloucester
I really liked George's Marvellous Medicine because it was soooooooooooo FUNNY.
Finlay, 8, Scotland
My favourite book is Matilda because she has magic powers.
Lucie, 6, Motherwell
Hello Newsround my favourite book by Roald Dahl is Esio Trot because it is funny and the movie is THE BEST lol.
We had a vote in our class and found that the most popular book was The BFG!
Class 4A at Ninian Park Primary School, Cardiff
We all love Roald Dahl and are currently reading the classic Matilda but, after a class vote we decided that the BFG was our overall favourite Roald Dahl book.
Dean Park Primary School P4a, Edinburgh
My favourite Roald Dahl book is Esio Trot.
Jessica, 15, London
My favourite Roald Dahl book is Charlie and the Chocolate Factory because I like the describing in the book with great interest.
Wajdan, 9, London
My favourite Roald Dahl book is the BFG because it's got really nice pictures and fantastic made up words.
Ryan, 9, London
My favourite Roald Dahl book is Charlie And The Chocolate Factory because it has lovely pictures in the book that I love.
Jason, 9, London
My Roald Dahl book is Charlie and the Chocolate Factory because I like sweets and chocolate so much that I wish I lived there.
Erika, 9, London
My favourite Roald Dahl book is BFG. I like it because the pictures are fantastic.
We are celebrating Roald Dahl day at our school and everyone is dressed up as their favourite character! We love Roald Dahl's stories and have shared our favourites today. Some of us like Fantastic Mr Fox because he is smart and funny! Some of us prefer James and the Giant Peach because it is like stepping into another world!
From 4SC, Firs Primary School, Manchester.
We are a primary 3/4 class and we have been reading the BFG as a book study! We think the book is just wondercrump and whoopsy-splunkers!
Primary 3/4 at Aberlady Primary School, Scotland
We had a vote in our classroom and our favourite book is the BFG.
2J, Woodside School, Shropshire
We like lots of his books but voted Charlie and the Chocolate Factory best. We are listening to George's Marvellous Medicine at the moment.
Stars Group, Bridgwater and Taunton College
My favourite books are Charlie and the Great Glass Elevator and Matilda. I also liked reading Boy. Roald Dahl's life looked very fun!
Arshiya, 9, Sheffield
The Twits, I enjoyed this book.
Justin, 16, Shetland
The Enormous Crocodile is my favourite book.
Jack, 15, Shetland
My favourite Roald Dahl book is The BFG I love it because the BFG is kind and gentle giant he also makes up his own words.
Alex, 9, London
Charlie and the Chocolate Factory.
Danny the Champion of the World
We love Roald Dahl. Our favourites are: The BFG, Charlie and The Chocolate Factory, The Twits, Fantastic Mr Fox and The Witches!
Elie Primary School, Fife
I like Matilda because it shows that girls can be really strong and clever.
Akshita, 10, Milton Keynes
I like The Witches because it's exciting and funny.
Sophia, 9, Perth
I like Charlie and the Chocolate Factory because Augustus Gloop is epic!
Jake, 9, Perth
I like Matilda because I would like her superpowers.
Alisa, 9, Perth
I like Fantastic Mr Fox because there is 'action' in it!!!
Harvey, 9, Perth
I like The Twits because they play nasty tricks on each other and it ends up being funny.
Ella, 9, Perth
I like George's Marvellous Medicine because when he makes the stuff it goes all wrong.
Zach, 9, Perth
I like Matilda because Matilda and I have lots in common.
Leah, 9, Perth
I like Charlie and the Chocolate Factory because the Oompa-Loompas make me laugh!
Chris, 9, Perth
I like the BFG because it is so funny!
Jack, 9, Perth
I like the BFG because it's imaginative.
Summer, 9, Perth
I like Esio Trot because its funny and a great story.
Jasmine, 9, Nottingham
My favourite book is the BFG because I think it is the funniest book ever.
My favourite book is Danny Champion of the World.
I like James and the Giant Peach because James is my Dad's name.
My favourite book is the BFG.
The Twits because it's really funny and the monkeys get their payback.
Kira 9, Hertford
Matilda because it is full of twists and turns.
Taylor, 9, Hertford
The Magic Finger because its about a girl who loves nature and so do I.
Georgie-May, 9, Hertford
I love James in the Giant Peach.
We are learning about the splendiferous author, Roald Dahl today! We really enjoyed watching the Newsround video clip 'Who was Roald Dahl and how did he write his books?' As a class, we voted Matilda as our favourite Dahl book! Charlie and the Chocolate factory was a close second.
Year 5, Wimbledon High School, London
My favourite Roald Dahl book is Charlie and the Chocolate Factory
Jake, 9, London
My favourite book from Roald Dahl is Charlie and the Chocolate Factory. I am so excited today because our lunch is going to be called with names from Roald Dahl's food (Pishlets fruity flapjacks, George's marvelous minitrees…)
Charlotte, 9, London
My favourite Roald Dahl book is Danny Champion of the world.
Olivia, 9, Lancaster
My favourite Roald Dahl book is Fantastic Mr Fox and my favourite character is boggis.
Lilly, 9, West Midlands
At my school we are watching Charlie and the Chocolate Factory ,and my favourite Roald Dahl book is the BFG.
My favourite Roald Dahl book is George's Marvellous Medicine but I also like the others because they are funny!
Lucie, 10, Derbyshire
My favourite book is the BFG
My favourite book is Matilda
Millie-may, 10, Derbyshire
l love James and the Giant Peach because its funny and has great characters.
Maddi, 9, Torquay
The Magic Finger is my favourite book. I would love to have magic power.
James, 5, Chichester
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