Dermot O'Leary hosts the first of the live shows. The remaining 16 acts will perform to impress judges Simon Cowell, Louis Tomlinson, Robbie Williams and Ayda Williams - as well as the viewing public at home. This year, Simon will be coaching the Girls, Louis has the Boys, Robbie will take on the Groups and Ayda has the Overs.
Each X Factor judge is in charge of a different section of singers on the show. The judges do not know what section of the competition they will be in charge of until the audition process has finished. Each judge then has to pick four acts to take forward to the live section of the show. Each week the two acts with the lowest amount of public votes have to sing again in a final showdown after which the judges decide who should be eliminated. Once there are only five acts left remaining it becomes left to the public to decide who should go.