Thriller is the sixth studio album by American recording artist Michael Jackson. The album was released on November 30, 1982 by Epic Records as the follow-up to Jackson's critically and commercially successful 1979 album Off the Wall. Thriller explores similar genres to those of Off The Wall, including funk, disco, soul, soft rock, jazz and pop. However, Thriller's lyrics deal with generally darker themes, including paranoia and the supernatural. It is also the best-selling album of all time. With a production budget of $750,000, recording sessions took place between April and November 1982 at Westlake Recording Studios in Los Angeles, California. Assisted by producer Quincy Jones, Jackson wrote four of Thriller's nine tracks. Following the release of the album's first single "The Girl Is Mine", some observers assumed Thriller would only be a minor hit record. With the release of the second single "Billie Jean", the album topped the charts in many countries. It reached number one in the United States and the United Kingdom simultaneously, becoming the first album to do so. At its peak, the album was selling a million copies a week worldwide. In just over a year, Thriller became the best-selling album of all time. Sales are estimated to be over 110 million copies sold worldwide as of March 2010. Seven of the album's nine songs were released as singles, and all reached the top 10 on the Billboard Hot 100. The album won a record-breaking seven Grammy Awards at the 1984 Grammys.