Today marks World Book Day, an annual event designed to encourage parents to read to their children.

As well as hundreds of reading events taking place around the world, many schools have also been marking the event by encouraging pupils to dress up as their favourite characters from literature, with Harry Potter and the Gruffalo being among the most popular costumes.

To celebrate, here below we list ten of the best book-related world records. 

Youngest -person -to -write -a -published -book ---GWR

Youngest person to write a published book 
The youngest commercially published female author is Dorothy Straight (b. 25 May 1958), of Washington, DC, USA, who wrote How the World Began in 1962, aged 4. It was published in August 1964 by Pantheon Books. More recently, the record for the youngest published male author is 5 years and 302 days and was achieved by Brazil's Adauto Kovalski da Silva (pictured above) who released his book Aprender é Fácil on 15 October 2005.

Staff from United Biscuits UK sales team marked their annual sales conference earlier this year by successfully toppling an arrangement of 5,318 Guinness World Records 2015 annuals at Old Windsor in Berkshire.

Check out the record-breaking topple in the player below, and read more about the attempt here.

Largest book signing
The most books signed by one author in a single session is 6,786 by Orrin Woodward (USA), who signed his book "And Justice For All" at Nationwide Arena in Columbus, Ohio, USA, on 21 June 2014. The attempt took 6 hours and 33 minutes to complete.

Highest earning adult fiction author
In terms of book sales and earnings, Erika Leonard James (published as E L James) is the most successful author of adult fiction. During the period June 2012 to June 2013, the British author netted a cool US$95million, beating previous record holder – the American writer James Patterson, who finished the 12-months with an almost-as-impressive US$91m.

Fastest selling book of fiction in 24hours
The fastest selling book in history is Harry Potter and the Deathly Hallows, the seventh - and final - novel in JK Rowling's (UK) Harry Potter series, which sold 8.3 million copies in the first 24 hours (or 345,833 books per hour), following its release in the USA at 00.01 on 21 July 2007.

Rowling also holds the record for Highest annual earnings for a children's author having notched up an estimated US$300 million (£150 million) between in 2007-2008 according to the Forbes Celebrity 100 list released on 11 June 2008.

Largest collection of books owned privately
John Q. Benham of Avoca, Indiana, USA has a private collection of over 1.5 million books.

As they have filled up his house, most of them must be kept in his six-car garage, two-storey building and piled under tarpaulin outdoors.

Marathon -reading -aloud

Longest marathon reading aloud
The longest marathon reading aloud is 113 hours 15 minutes achieved by Deepak Sharma Bajagain (Nepal) at the Tudikhel Ground, Kathmandu, Nepal, from 19 to 24 September 2008.

He recited 17 different books from 13 authors during his record attempt.

Most abandoned book
The most abandoned book is Simon Cowell: The Unauthorised Biography by Chas Newkey-Burden. A 2010 survey of thousands of books left behind by guests at 452 Travelodges in Britain revealed that the X Factor star's biography topped the list. 

High Library Collage

Highest library
The world's highest library is located on the 60th floor of the JW Marriott Hotel at Tomorrow Square in Shanghai, China, at 230.9 m (757 ft 6 in) above street level.

Membership is available to the public, and the 103 shelves in the library contain an ever-expanding collection of Chinese and English books.

GWR Bookshelf

Best-selling copyright book
And finally, a record of our own that we're all very proud of at Guinness World Records HQ.

Excluding non-copyright works such as the Bible (with an estimated 6 billion copies sold) and the Koran, the world's all-time best-selling book is Guinness World Records (formerly The Guinness Book of Records).

Since it was first published in October 1955, global sales in some 37 languages have exceeded 124 million as of October 2010.