Bobby Ray Simmons Jr. (born November 15, 1988), known professionally as B.o.B, is an American rapper, singer, songwriter, and record producer.

Raised in Decatur, Georgia, Simmons signed with record producer Jim Jonsin's Rebel Rock Entertainment in 2006. Two years later, he signed a joint venture recording contract with fellow Georgia rapper T.I.'s Grand Hustle Records, an imprint of Atlantic Records. Following his major-label deal, Simmons quickly achieved commercial success when his 2009 single, "Nothin' on You" (featuring Bruno Mars), topped the U.S. Billboard Hot 100 chart and received three nominations—Record of the Year, Best Rap Song, and Best Rap/Sung Collaboration—at the 53rd Grammy Awards.

His 2010 follow-up singles, "Airplanes" (featuring Hayley Williams of Paramore) and "Magic" (featuring Rivers Cuomo), peaked at numbers two and ten on the Billboard Hot 100, respectively. All three preceded the release of Simmons' debut studio album The Adventures of Bobby Ray (2010), which was promoted by two extended plays (EPs) and several self-released mixtapes. The album peaked atop the Billboard 200, received double platinum certification by the Recording Industry Association of America (RIAA), and saw critical praise for its blending of alternative hip hop, pop rap, and rock. Simmons was named the ninth "Hottest MC in the Game of 2010" by MTV on their annual list. The following year, he guest appeared on English singer Jessie J's 2011 single "Price Tag", which peaked atop the UK Singles Chart and at number 23 on the Billboard Hot 100.

Simmons' dubstep-influenced 2011 single, "Strange Clouds" (featuring Lil Wayne), became his fourth top-ten hit on the Billboard Hot 100. It served as lead single for his second studio album of the same name (2012), which peaked at number five on the Billboard 200 and spawned the follow-up singles "So Good" and "Both of Us" (featuring Taylor Swift), both of which peaked within the top 20 in the US and received platinum certifications by the RIAA. His third studio album, Underground Luxury (2013), explored darker subject matter and adopted a grittier tone, spawning the club-oriented singles "HeadBand" (featuring 2 Chainz) and "We Still in This Bitch" (featuring T.I. and Juicy J); the album was met with a critical and commercial decline. That same year, he guest appeared on the platinum-certified singles "Paranoid" by Ty Dolla Sign and "Up Down (Do This All Day)" by T-Pain.

Dissatisfied with his lack of promotion from the label, Simmons released his twelfth mixtape, Psycadelik Thoughtz (2015), as his final project for Atlantic. His compilation album Elements (2016)—released by his own label, No Genre—was compiled from four mixtapes which delved into political subject matter and conspiracy theories. His 2016 single, "Flatline", was a diss song aimed at astrophysicist Neil deGrasse Tyson, in which Simmons endorsed modern flat Earth beliefs. His fourth album, Ether (2017), served as his first independent album and narrowly entered the Billboard 200.