* No central database: There's no global registry or library that tracks every single book ever published.
* Self-published books: With the rise of self-publishing, countless books are printed without going through traditional publishing houses, making them difficult to track.
* Limited access: Many books exist in private collections, libraries, or archives that aren't publicly accessible.
* Definition of "book": What constitutes a "book" is subjective. Do we count pamphlets, magazines, ebooks, or even manuscripts?
Estimates:
While an exact number is impossible, some estimates exist:
* A 2017 study by the University of Oxford estimated that there were 130 million unique titles in the world.
* A 2010 estimate by the Library of Congress placed the number of books published annually at over 1.5 million.
The Takeaway:
While we can't know the exact number of books in the world, it's safe to say there are billions of books in existence.