Louisa Johnson becomes youngest X Factor winner

Louisa Johnson has become the youngest person to be crowned the winner of the UK X Factor.

The 17-year-old student from Essex beat Cheryl Fernandez-Versini's duo Reggie 'N' Bollie to clinch the title at a star-studded show at the SSE Arena in Wembley.

Following the announcement she said: "I've imagined this day for so many years and you have no idea how much this means to me."

Her rendition of Bob Dylan's Forever Young had judge Simon Cowell saying: "Congratulations... we are witnessing the birth of a star."

Louisa's mentor, singer and judge Rita Ora, said: "I love you... no matter what happens you're a superstar and you're so great. There is a reason this show is so good because look at what it can create, so thank you very much."

The final show saw both acts perform the winner's single and their favourite song from the series.

Louisa performed her favourite song, It's A Man's Man's Man's World, which saw Ora running on stage to hug her after the performance.

Cowell told her: "That is what is called The X Factor. I mean seriously... I know I'm prone to exaggeration, I can honestly say in all the years I have done this show, I have never heard anything as good as what you just did... you are not human."

Ghanaian duo Reggie 'N' Bollie performed their mash-up rendition of One Direction's What Makes You Beautiful and Reel 2 Real's I Like To Move It.

An emotional Fernandez-Versini told them: "I've believed in you from day one, thank you from the bottom of my heart. I love you so much."

The duo thanked their fans, saying: "We want to say thank you to everyone supporting us, thank you to the judges - thank you for making us live our dreams, thank you Cheryl for for your belief, we really appreciate it."

The show marked the last live performance by boy band One Direction before they take a break. After their song Infinity, Cowell thanked the band for the last five years, before playing them messages from a host of celebrities.

Among the stars who recorded short messages for the band were James Corden, Robbie Williams, Wayne Rooney, Danny De Vito, Jack Whitehall and Little Mix. Footballer David Beckham was filmed singing along to one of their songs in the car, before saying to them: "Congratulations, you've given us years of incredible moments and you need to come back soon."

The band performed a second song, History, before hugging each other.

Liam Payne told the show's host Olly Murs: "It's been the most amazing five years... we want to thank Simon, The X Factor... we are sad to be going away for a little while but we need it, thank you to all the fans who've supported us over the years."

Global star Adele also performed her new single and showed off a new, shorter hairdo.

Following her song she laughed, saying: "That was amazing," and told Murs: "Honestly I've been waiting half my life to do this. I'm so excited to be here. Thanks for having me, I loved it. I wanted to burst out laughing, I did at the end."

Talking about The X Factor finalists, she said: "I love all of them, I'm going to call Louisa but Lauren was my favourite, I loved her."

When Murs asked her what advice she would give the contestants, she said: "Always go with your own instinct. I've always gone on what I thought."

The first guest performance was by Coldplay, who performed their new song Adventure Of A Lifetime.

They were joined on stage by people dressed as monkeys and as presenter Caroline Flack joined lead singer Chris Martin on stage she said: "Oh you're so sweaty," following it up with: "That was amazing, I love your monkeys."

"We're so happy to be here," Martin said.

He admitted being a big fan of the show, saying he had watched Saturday night's edition. "It was wonderful, it made me nervous for everybody," he said.

Asked if he had a favourite, he said: "I think they are both wonderful. I think if you make it this far you're doing something really well. We're so happy to be here."

Global superstar Mariah Carey recorded a good luck video message for the contestants in which she joked at the end: "One thing you shouldn't do is listen to anything Simon Cowell says... Hi Simon."

All of the finalists returned to open the show with a group rendition of Downtown.