Idol (also known as SuperStar in some countries) is a reality television singing competition format created by British television producer Simon Fuller and developed by Fremantle. The format began in 2001 with the British television series Pop Idol; its first adaptation was the Polish series Idol in 2002. It has since become the world's most widely watched television franchise, as well as one of the most successful entertainment formats, adapted in over 56 regions around the world, with its various versions broadcast to 150 countries with a worldwide audience of roughly 3.2 billion people. The franchise has generated more than $2.5 billion in revenue.

Each season, the series aims to find the most outstanding unsigned solo recording artist (or "idol") in a region. Originally aimed for pop singers, the series has since evolved to accept singers from different genres of music, such as rock, R&B, and country. Through a series of mass auditions, a group of finalists are selected by a panel of judges (which usually consists of artists and record producers) who offer critiques on their performances. The finalists then advance to the weekly live shows. On each live show, the contestants all sing, the television audience votes (by telephone, SMS Internet, and via apps), and then the contestant who receives the fewest votes gets eliminated. The final episode is the grand finale episode, when usually two, but sometimes three or four, finalists are left, and the contestant who gets the largest number of votes is declared the winner. The winner receives a recording contract, monetary prizes, and a title as their nation's "Idol", "SuperStar" or "Star". Sometimes one or more of the runners-up get recording contracts as well.

The various series have launched the careers of a number of highly successful recording artists around the world, including Idol winners Will Young of the United Kingdom, Kelly Clarkson, Carrie Underwood, Scotty McCreery, Fantasia, Ruben Studdard, David Cook, and Phillip Phillips of the United States, Kurt Nilsen of Norway, Ryan Malcolm and Kalan Porter of Canada, Guy Sebastian of Australia, and Elvis Blue of South Africa. Contestants who did not win but have still gone on to prominence include Anthony Callea, Ricki-Lee Coulter and Jessica Mauboy of Australia, Jacob Hoggard and Carly Rae Jepsen of Canada, and Clay Aiken, Chris Daughtry, Gabby Barrett, Lauren Alaina and Adam Lambert of the United States, among many others. Some Idol contestants have also achieved success in acting and musical theater such as Melissa O'Neil of Canada, and most notably Academy Award winner Jennifer Hudson of American Idol.