The cover of The Da Vinci

Author Dan Brown's The Da Vinci Code has sold more than eight million copies worldwide in little over two years, while his previous novels remain on best-seller lists around the world.

According to his personal website, 39-year-old Dan Brown gets up and starts writing each day at four in the morning. He writes with an antique hour glass on his desk and at the end of each 60 minute period he does sit-ups, stretches and push-ups .

He also confesses to wearing gravity boots, saying: "Hanging upside down seems to help me solve plot challenges by shifting my entire perspective."

He does not explain whether being upside down helped him develop his book The Da Vinci Code, but a rush of blood to the head seems to have transformed Brown from run-of-the-mill thriller writer to global phenomenon.

The Da Vinci code is a classic whodunit , which centres on a global conspiracy surrounding the Holy Grail mythology and places heavy emphasis on symbols and cryptography .

Protagonist Robert Langdon, a Harvard professor likened to a contemporary Indiana Jones, also appeared in Brown's second book Angels and Demons.

The book mixes art history with mythology, semiotics with medieval history - and though it does not sound like a potent mix, it has proved gripping to millions of readers around the world.

British reviewer Mark Lawson described it as "irritatingly gripping tosh", while other reviewers praised its mix of conspiracy theories and a fast-paced narrative.

Until 1996, Brown was an English teacher at an exclusive US school. He gave up his job to write full-time when he read a Sydney Sheldon novel on holiday and felt he could do better.

His first book Digital Fortress was a colour-by-numbers affair and sold moderately well.

His subsequent books Angels and Demons and Deception Point continued to sell adequately, but few could have predicted the hysteria that would surround The Da Vinci Code.

Like all his books, it centres on secret societies, global conspiracies, codes and symbols.

The book went to the top of the New York Times book list in its first week on release, and its success helped push sales of Brown's earlier books.

Earlier this year all four of his novels were in the New York Times best-seller list.

The Da Vinci Code has been translated into 42 languages and has spawned its own cottage industry of publications, including guides on to how to read the book, rebuttals and counter claims.

Brown himself admits that the success of the book has taken him by surprise.

He told his website: "I never imagined so many people would be enjoying it this much. I wrote this book essentially as a group of fictional characters exploring ideas that I found personally intriguing."

He says the idea for the book stems from studying art history at the University of Seville in Spain, where he learnt about "the mysteries of Da Vinci's paintings".

(Agencies)

sit-up: an stomach exercise in which a person sits up from a supine position without using the arms for leverage（仰臥起坐）

push-up: an arm exercise performed lying face to the floor and pushing the body up and down with the arms（俯臥撐）

run-of-the-mill: not special in any way（普通的）

whodunit: a story about a crime (usually murder) presented as a novel or play or movie（偵探小說）

cryptography: the science of analyzing and deciphering codes and ciphers and cryptograms（密碼術）

protagonist: the principal character in a work of fiction（主角，領導者）

semiotics: a philosophical theory of the functions of signs and symbols（記號語言學）

hysteria : state of violent mental agitation（歇斯底里）