"One Time" is the debut song of Justin Bieber. It is the first single released from his debut EP, My World. It was first solicited to mainstream and rhythmic radio on May 18, 2009. It was released via digital download in the United States and Canada on July 7, 2009, and was released in several other countries during autumn 2009. An acoustic version of the song, called the "My Heart Edition" was released to iTunes on December 22, 2009. The song, moderately paced with R&B, pop, and hip-hop influences, is an ode to young love.
The music video, directed by Vashtie Kola, was posted by Bieber on his YouTube channel on June 13, 2009, almost a month before the single was released to iTunes. Bieber's mentor, Usher and one of his closest friends, Ryan Butler make appearances in the video. It features Bieber clad in a grey hooded sweatshirt grinning mischievously into the camera.[ As of August 2016, the video had been viewed over 480 million times on YouTube. Bieber made a comment stating "It was really cool going from my webcam to professional videos". In a review of the video Entertainment Weekly's Leah Greenblat said: "Bieber does seem to share many of the qualities that made his idols the pop/R&B superstars they've become, including a clear, supple voice, pinup-boy looks, and bona fide instrument skills".
In the music video, Usher, Bieber and Butler all portray themselves as the latter two are at Usher's house playing video games. Bieber receives a phone call from Usher, in which he asks him if could he watch the house until he gets back. After agreeing, Bieber holds a house party and tries to get close to one girl in particular, played by Kristen Rodeheaver, but is disappointed because he thought they were bonding but at the end of the video when they are sitting together at the pool, she kisses him on the cheek, then leaves. Originally, Rodeheaver and Bieber were supposed to hold hands and jump into the pool, but it was too cold. He then stands up and gets caught by Usher.
My Heart EditionLove Me" would be released. Bieber later on announced on December 19, 2009, that an "exclusive unplugged Christmas version" of "One Time" would be released to iTunes the following Tuesday. The song was released a day early on December 21, 2009. The cover art for the single features a still from the music video from "One Less Lonely Girl". Kyle Anderson of MTV stated that the song "strips away the original track's synths and technology and leaves only Bieber's able voice". Bieber performed the acoustic version of the song when he guest starred on True Jackson, VP, during a live session with MTV, and on Blue Peter. It is featured on the Radio Disney Jams, Vol. 12 album.
An acoustic version of "One Time" appeared on Justin's album, My Worlds Acoustic.
This song appears on the Japanese edition of the album Never Say Never: The Remixes.