Short answers, pulled from the story.
The X Factor premiered on ITV on the 4th of September 2004. It ran for fifteen series and around 445 episodes before its final episode in December 2018, with ITV formally confirming cancellation on the 28th of July 2021.
The X Factor was created by Simon Cowell, who devised the format in 2004 following his experience as a judge on Pop Idol. Cowell wanted to own the television rights to the new competition, giving him greater control over contestants' progress than he had held on Pop Idol.
The winner received a recording contract with Syco Music worth one million pounds. From the fifth series onward, this included a 150,000 pound cash advance, with the remaining balance allocated to recording and marketing costs.
One Direction, Little Mix, JLS, Olly Murs, and Ella Henderson all reached number one in the UK charts after appearing on The X Factor. The show produced 35 number-one singles in total, including ten winners' singles and 21 further chart-toppers by other contestants.
Viewing figures fell by more than 50 percent between the peak of 14 million average viewers in 2010 and the final series in 2018, which averaged 5.75 million. ITV announced on the 28th of July 2021 that it had no current plans for another series, citing a format described as having gone slightly stale.
In 2009 a Facebook campaign successfully pushed Rage Against the Machine's "Killing in the Name" to the Christmas number one spot ahead of X Factor winner Joe McElderry's single. McElderry's single reached number one the following week, but the campaign reflected growing public hostility to the show's annual dominance of the Christmas chart.