O is the debut studio album by American R&B singer Omarion, released on February 22, 2005 via Epic Records and Sony Urban Music. Despite featuring explicit language, the album doesn't have a Parental Advisory label on the cover. It features three singles: the title track, "Touch" and "I'm Tryna." The album entered at number one on the Billboard 200, and has sold more than 750,000 copies in the United States as of November 2008. O went on to be certified Gold by the Recording Industry Association of America (RIAA) and was nominated for a Grammy Award for Best Contemporary R&B Album at the 48th Grammy Awards.

"O" is a song by American singer Omarion. It was released on August 17, 2004, as the lead single from his debut album of the same name. "O" was the first choice for Omarion's debut single in the UK and was picked over "Touch", which was the original choice for his first UK single. The song was Omarion's first hit as a solo artist, peaking at number 27 on the US Billboard Hot 100. It also reached numbers 12 and 24 on both the Hot R&B/Hip-Hop Songs and Mainstream Top 40 charts respectively. The song also charted in New Zealand and the UK, peaking at numbers 18 and 47 respectively.