Books, with their ability to educate and entertain, have proved almost indispensable since Gutenberg perfected the printing press in 1440.
The importance of the written word is only underlined by Google Book's estimate that approximately 130 million good reads had been published in the intervening centuries.
Such completion means only a select few of the very best books have been read in record numbers.
Note, there is no single source consistently tracking book sales over the centuries and religious books such as the Bible and Quran have been omitted, as so many are disturbed for free.
Read on to learn the best-selling individual books and book series to date in any language.
30. The Hite Report (50 million)
The Hite Report helped redefine our understanding of the female sexual experience and the book is still considered essential reading for women of all ages.
First published in 1976, Dr. Hite's book is believed to be the first scientific analysis to focus specifically on women's sexuality.
29. Watership Down (50 million)
Richard Adams originally began telling the story of a small band of rabbits in search of a safe home to his two daughters, who insisted he published his tales as a book.
Watership Down quickly became a huge hit with both children and adults, and the book won a pair of prestigious prizes when published in 1972.
28. The Eagle Has Landed (50 million)
Jack Higgins' 1975 thriller involves an elite team of Nazi paratroopers arriving in the UK to abduct Winston Churchill and cripple the Allied war effort.
The work of fiction proved so popular, the book was adapted into an equally successful movie the next year.
27. The Name of the Rose (50 million)
The 1980 debut novel by Italian author Umberto Eco is a historical murder mystery set in an Italian monastery in the year 1327.
The book quickly became a commercial and critical success after it was translated into English and other languages three years later, and a big-budget movie adaption arrived in 1987.
26. Black Beauty (50 million)
Composed by author Anna Sewell during the final years of her life, the book is an autobiographical memoir told by the titular horse named Black Beauty.
Despite dying only months after its publication, Sewell survived long enough to see her only novel become a publishing phenomenon.
25. Anne of Green Gables (50 million)
The beloved classic 1908 novel concerns an orphan girl's arrival into a world of privilege.
Canadian author L.M. Montgomery's episodic novel is today considered one of the greatest children's novels of the mid-twentieth century.
24. Common Sense Book of Baby & Child Care (50m)
The Common Sense Book of Baby and Child Care is a book by American pediatrician Benjamin Spock.
The book's core message of parents trusting their own common sense was considered revolutionary at the time of its publication in 1946.
23. Heidi (50 million)
Despite being written and published more than one hundred years ago, Heidi remains a perennial favorite for children.
Johanna Spyri's classic book relays the adventures enjoyed by orphan Heidi after she is sent to live in the Swiss Alps.
22. Lolita (50 million)
Lolita is the highly controversial 1955 novel written by Russian-American novelist Vladimir Nabokov.
The plot finds a middle-aged man becoming besotted by twelve-year-old girl Lolita before the pair go on the run.
21. One Hundred Years of Solitude (50 million)
Nobel Prize-winning author Gabriel García Márquez's landmark novel tells the story of the Buendia family over several generations.
The book's rich and evocative prose has come to define an entire genre known as "magical realism."
20. You Can Heal Your Life (50 million)
This self-help book's key message is: "If we are willing to do the mental work, almost anything can be healed."
However, the theories described in this book have been criticized as groundless by proponents of evidence-based medicine.
19. Ben-Hur: A Tale of the Christ (50 million)
Published in 1880, Lew Wallace's Ben-Hur is considered one of the most popular and beloved 19th century American novels.
This faithful New Testament tale intertwines the life of Jesus and a man who finds redemption for himself and his family.
18. The Bridges of Madison County (60 million)
The Bridges of Madison County is a 1992 best-selling romance novella by American writer Robert James Waller.
The book tells the story of a married but lonely woman who encounters and falls in love with a free-spirited photographer.
17. The Catcher in the Rye (65 million)
This J.D. Salinger novel published in 1951 details two days in the life of 16-year-old Holden Caulfield.
Although controversial at the time of publication for its frank language, the book became an instant bestseller and a schoolroom classic.
16. The Alchemist (65 million)
Author Paulo Coelho's visionary blend of spirituality, magical realism and folklore has topped bestseller lists in 74 countries.
The global phenomenon follows a young shepherd as he embarks on a journey and documents the life-changing wisdom he learns on the way.
15. Harry Potter and the Deathly Hallows (65 million)
The final novel of the Harry Potter series was released in July 2007.
The fantasy finds the protagonist and his teenage companions enter the final struggle with Voldemort.
14. Harry Potter and the Half-Blood Prince (65 million)
The penultimate novel in the Harry Potter series was released in July 2005.
The story picks up during Harry's sixth year at Hogwarts, as Voldemort's power and followers increase.
13. Harry Potter & the Order of the Phoenix (65 million)
The Order of the Phoenix is the fifth book in the Harry Potter fantasy series.
The book finds 15-year-old Harry in adolescence, complete with outbursts of rage, a growing crush and a powerful sense of rebellion.
12. Harry Potter and the Goblet of Fire (65 million)
The Goblet of Fire is author J. K. Rowling's fourth novel in the Harry Potter series.
The protagonist faces death-defying tasks, dragons and dark wizards with the help of his best friends Ron and Hermione.
11. Harry Potter & the Prisoner of Azkaban (65 million)
The third in the Harry Potter series follows the young wizard in his third year at Hogwarts.
The book opens with a tense atmosphere at the school for wizards, due to an escaped mass murderer on the prowl.
10. Harry Potter & the Chamber of Secrets (77 million)
The Chamber of Secrets is the second in British author J. K. Rowling's popular fantasy series.
Students at Hogwarts are found as though turned to stone, appearing to prove house-elf Dobby's gloomy prophesy true.
9. The Da Vinci Code (80 million)
Harvard symbologist Robert Langdon races against time to decipher a labyrinthine puzzle before an explosive ancient truth is lost forever.
The 2003 mystery thriller novel by Dan Brown proved extremely popular with readers for its lightning-paced plot.
8. The Adventures of Pinocchio (80 million)
Animated puppet Pinocchio enjoys many adventures after magically coming alive.
First published in 1883, author Carlo Collodi's classic tale about redemption and parenthood still appeals to both children and adults.
7. She: A History of Adventure (83 million)
The plot finds academic Horace Holly and his ward Leo Vincey journeying to a lost kingdom in the African interior.
Author H. Rider Haggard's romantic adventure proved extraordinarily popular upon its release in 1887 and the book has never since been out of print.
6. The Lion, the Witch and the Wardrobe (85 million)
A quartet of adventurous siblings step through a wardrobe door into the land of Narnia, a land frozen in eternal winter and enslaved by the power of the White Witch.
This book is by far the most popular in the classic Chronicles of Narnia fantasy series, written by Cambridge academic C.S. Lewis.
5. And Then There Were None (100 million)
An incongruous assortment of guests is assembled on a remote island and then killed off one by one.
This ingenious book topped a recent poll marking Agatha Christie's 125th birthday year to discover which of her 80 crime books was the world's favorite.
4. Dream of the Red Chamber (100 million)
Written sometime in the middle of the 18th century during the Qing dynasty, this epic follows the infatuations and adventures of a pubescent boy.
The book has been described by critic Anthony West as "one of the great novels of world literature [... ] to the Chinese as Proust is to the French or Karamazov to the Russians."
3. The Little Prince (100 million)
Antoine de Saint-Exupéry's book follows a young royal as he travels across the universe.
This deceptively simple fable has captured the imaginations of both adults and children ever since it was first published in the 1940s
2. Harry Potter and the Sorcerer's Stone (120 million)
J.K. Rowling's first book of the fantasy series finds eleven-year-old orphan Harry Potter discover he is a wizard, who is then invited to study at Hogwarts.
However, even as the protagonist escapes his ordinary life to enter a world of magic, he finds trouble waiting for him.
1. The Hobbit (140.6 million)
The Hobbit, or There and Back Again is J. R. R. Tolkien's children's fantasy novel published in 1937.
The Lord of the Rings prelude has remained in print continuously to entertain successive generations of readers, while the book's hero, Bilbo Baggins, is one of the most popular characters of fiction.
