Coldplay's Viva La Vida or Death and All His Friends was the best-selling album of 2008 worldwide.
Figures released today from the IFPI - the International Federation of the Phonographic Industry - showed that the award-winning album sold 6.8m copies across the world.
It also sold more downloads than any other album in digital history within a month of its release in June.
Rockers AC/DC came in at number two with their 15th studio album Black Ice, while the soundtrack to Mamma Mia! The Movie, secured the number three spot.
The IFPI figures showed that four of the top 10 albums were by British artists, with Duffy at number four with her debut album Rockferry.
She was also found to be the biggest-selling new artist worldwide last year.
Metallica's ninth studio album Death Magnetic took fifth place, while Leona Lewis and Amy Winehouse were sixth and seventh respectively with Spirit and Back to Black.
The soundtrack to High School Musical 3: Senior Year was the eighth best-selling, Lil Wayne's Tha Carter III came in at nine and Rihanna's Good Girl Gone Bad wrapped up the top ten.