LOS ANGELES (Reuters) - U.S. television talent show "American Idol," in which viewers choose the nation's next pop star, reaches its eighth season climax this week with a finale between musical theater performer Adam Lambert, 27, and guitar- and piano-playing student Kris Allen, 23.
The show is the most watched television show in the United States, averaging 26.3 million viewers per episode this year over its five-month run.
Following are some facts about "American Idol."
* "American Idol" first ran in the summer of 2002 as an adaptation of the British hit TV show "Pop Idol." The winner gets a recording contract.
* The show's viewer-driven format has produced bona fide stars from its winners, including Grammy winners Kelly Clarkson and Carrie Underwood.
Viewers vote through telephone lines and by text message, often multiple times. Each week the contestant with the lowest number of votes is eliminated. In last year's finale, a record 97.5 million votes were cast.
* The three regular judges -- U.S. music producer Randy Jackson, former pop star Paula Abdul and British record producer Simon Cowell -- were joined this year by songwriter Kara DioGuardi.
* Other former contestants who have capitalized on their fame include Chris Daughtry, whose band Daughtry made a multi-platinum debut album; Jennifer Hudson, who won an Oscar for the movie "Dreamgirls"; Fantasia Barrino, who starred in "The Color Purple" on Broadway; and Clay Aiken, who appeared in musical "Spamalot" on Broadway.
"American Idol" is a joint production of 19 Entertainment, a unit of CKX Inc and Fremantle Media, a division of British-based RTL group which is controlled by media giant Bertelsmann AG.
The show is broadcast in the United States on the Fox television network, a unit of Rupert Murdoch's News Corp. It is broadcast live or tape-delayed to more than 100 countries, including Pakistan, Israel, United Arab Emirates, China, Australia and South Africa.
Reporting by Jill Serjeant; Editing by Eric Walsh