who composed the song ?
It was written by Savan Kotecha and Carl Falk, instrumentation was done by Rami Yacoub and Carl Falk and Serban Ghenea handled the audio mixing.
What Makes You Beautiful
"What Makes You Beautiful" was written by Savan Kotecha and Carl Falk, and was produced by Yacoub and Falk. Instrumentation was completed by Falk and Yacoub. Serban Ghenea handled the audio mixing, Tom Coyne the audio mastering, and John Hanes the mix engineering, for which Phil Seaford served as the assistant. 
who sings what in what makes you beautiful The band - One Direction who are the members of this band ? Niall Horan, Liam Payne, Harry Styles and Louis Tomlinson. Zayn Malik was a former member. was the above mentioned song performed live ? Yes, a number of times.
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What Makes You Beautiful [SEP] Background and production
"What Makes You Beautiful" was written by Savan Kotecha and Carl Falk, and was produced by Yacoub and Falk. Instrumentation was completed by Falk and Yacoub. Serban Ghenea handled the audio mixing, Tom Coyne the audio mastering, and John Hanes the mix engineering, for which Phil Seaford served as the assistant. Discussing the song's conception, Kotecha said: After recording the song at Cosmos Studios and Kinglet Studios in Stockholm, Sweden, the band felt relieved to have a song that they were happy to release as their debut single. Band member Liam Payne called the song "perfect", and Harry Styles said, "When we were recording in the studio we knew instantly that we wanted this track to be our first single." Styles spoke to MTV News, "I think for us we wanted to release something that wasn't cheesy but it was fun.