Who is the author of the best selling book series in history?

Joanne "Jo" Rowling, ( born 31 July 1965), pen names J. K. Rowling and Robert Galbraith, is a British novelist, screenwriter and film producer best known as the author of the Harry Potter fantasy series. The books have gained worldwide attention, won multiple awards, and sold more than 400 million copies. They have become the best-selling book series in history and been the basis for a series of films over which Rowling had overall approval on the scripts and maintained creative control by serving as a producer on the final instalment.

Born in Yate, Gloucestershire, England, Rowling was working as a researcher and bilingual secretary for Amnesty International when she conceived the idea for the Harry Potter series while on a delayed train from Manchester to London in 1990. The seven-year period that followed saw the death of her mother, birth of her first child, divorce from her first husband and relative poverty until she finished the first novel in the series, Harry Potter and the Philosopher's Stone, in 1997. There were six sequels, the last, Harry Potter and the Deathly Hallows, in 2007. Since then, Rowling has written four books for adult readers: The Casual Vacancy (2012) and—under the pseudonym Robert Galbraith—the crime fiction novels The Cuckoo's Calling (2013), The Silkworm (2014) and Career of Evil (2015).