Billboard Year-End Hot 100 singles of 2009

"Drop It Like It's Hot" is a song by American rapper Snoop Dogg featuring fellow American musician Pharrell Williams. It was released on September 27, 2004, as the lead single from Snoop Dogg's seventh studio album, R&G : The Masterpiece (2005). The song was produced by the Neptunes. It is regarded as an iconic song, with Snoop performing the chorus and the second and third verses while Pharrell performs the first verse.

"Otherside" is a song by American rock band Red Hot Chili Peppers. It was released as the third single from their seventh studio album, Californication (1999), and confronts the battles addicts have with their prior addictions. The track was released in New Zealand in December 1999 and was given an international release in January of the following year.

"Where's Your Head At" is a song by British electronic music duo Basement Jaxx. It was released as the third single from their second album, Rooty, on 19 November 2001. The song is based on samples from Gary Numan's songs "M.E." and "This Wreckage". The song peaked at number nine in Canada and the United Kingdom, number 16 in Australia, and number 39 on the US Billboard Modern Rock Tracks chart, the band's only charting single on a non-dance music chart in the United States. The song ranked at number 83 on Pitchfork Media's list of the "Top 500 Tracks of the 2000s".

"Apologize" is a song written by Ryan Tedder, which first appeared on Timbaland's second studio album Shock Value (2007). It was then released as the third single from that album, along with the original recording by OneRepublic. It accordingly also served as the debut single for OneRepublic's debut album Dreaming Out Loud (2007), produced by Greg Wells. Timbaland's version omits the guitar solo after the second verse in the original, and includes an extra line of percussion, new backing vocals, and added sound samples, in addition to sound mixing and a few other minor changes. The song was the biggest radio airplay hit in the history of the Mainstream Top 40 chart in the United States, with 10,394 plays in one week, until its record was broken by Leona Lewis's "Bleeding Love", which was also co-written by Tedder. The song was a major hit internationally, reaching number one in 16 countries, including Australia, Austria, Canada, Germany, Italy, New Zealand, Sweden, Turkey, and the Netherlands, as well as staying at number one for eight consecutive weeks on the Billboard Pop 100 chart. The song peaked at number two on the Billboard Hot 100, staying in the top-10 for 25 weeks, and spent 13 weeks at number one in Canada.

"No One" is a song recorded by American singer-songwriter Alicia Keys for her third studio album As I Am (2007). It was written and produced by Keys and Kerry Brothers Jr., with additional writing by DJ Dirty Harry. The song was released as the lead single from As I Am on October 9, 2007, by J Records.

"Low" is the debut single by American rapper Flo Rida featuring fellow American singer T-Pain, from the former's debut studio album Mail on Sunday and also featured on the soundtrack to the 2008 film Step Up 2: The Streets. An official remix was made which also features Pitbull. The song peaked at number one on the U.S. Billboard Hot 100.

"Closer" is a song by American recording artist Ne-Yo. The song was produced by Stargate. It was released as the lead single from Ne-Yo's third studio album, Year of the Gentleman (2008).

Jordan Roseman, known professionally as DJ Earworm, is an American mashup artist from San Francisco, California, who has achieved recognition for his technically sophisticated, songwriting oriented music and video mashups. His annual “United State of Pop” mashup features the top 25 songs of the year, based in part on the Billboard's Year-End Hot 100 chart, in one mix.

"All Summer Long" is a song by American recording artist Kid Rock. It was released in March 2008 as the third single from his seventh studio album, Rock n Roll Jesus (2007). It samples Bob Seger's song "Night Moves", "Sweet Home Alabama" by Lynyrd Skynyrd and "Werewolves of London" by Warren Zevon.

"Use Somebody" is a song recorded by the American rock group Kings of Leon. It was the second single from the band's fourth studio album Only by the Night, and it entered American and British charts in early October 2008, three weeks after the album release. The single was augmented with a music video released a month later.

"Right Round" is a single performed by American rapper Flo Rida featuring guest vocals from American singer Kesha. It was released as the lead single from his second studio album, R.O.O.T.S. (2009). It was released to radio on January 27, 2009 and was digitally released on February 10 by Poe Boy Entertainment and Atlantic Records. The song heavily interpolates the chorus of the Dead or Alive song "You Spin Me Round " in its hook. According to one of the song's writers, the chorus refers to a stripper. Kesha contributed guest vocals to the song, but was uncredited in the United States and Canada during its run atop the charts.

"Down" is a song by British singer Jay Sean featuring American rapper and labelmate Lil Wayne. The song was released in North America as his debut single from his first album there, All or Nothing. In other markets, including the United Kingdom, the song serves as Jay Sean's lead single from his third studio album. Produced by J-Remy and Bobby Bass, "Down" is the seventh-best selling single of 2009 and has been certified Platinum in several countries. The song went on to sell six million copies in the United States and received a large airplay on radio worldwide.

"Need You Now" is a song recorded by American country music trio Lady A. The band co-wrote the song with Josh Kear, and produced it with Paul Worley. It serves as the lead-off single and title track to their second studio album of the same name, and was first released in the US on August 11, 2009, and it features lead vocals from both Scott and Kelley. The song also served as their debut single in the UK and Europe, where it was released May 3, 2010. It won four Grammy Awards in 2011, including for Song of the Year and Record of the Year, the only country song to win both honors since "Not Ready to Make Nice" by the Chicks won in 2006.

"Do You Remember" is the second single by British R&B artist Jay Sean from his American-debut album, All or Nothing. The song features Jamaican dancehall musician Sean Paul and American crunk rapper Lil Jon. The song was produced by J-Remy and Bobby Bass.

"Replay" is the debut single by British Virgin Islands singer Iyaz. It is the first single released from his debut album of the same name, which was released in 2009. The official remix features American rapper Flo Rida.

"All I Do Is Win" is a song from DJ Khaled's fourth studio album Victory (2010). It was the third single from the album. The track features American rappers T-Pain, Ludacris, Snoop Dogg and Rick Ross. It was released on February 8, 2010, along with "Put Your Hands Up". The song peaked at number 24 on the US Billboard Hot 100 chart. The single was certified triple platinum by the Recording Industry Association of America (RIAA).

"Airplanes" is a song by American rapper B.o.B featuring American singer Hayley Williams of Paramore. The song was released in April 2010, as the third single from his debut studio album, B.o.B Presents: The Adventures of Bobby Ray. B.o.B co-wrote the song alongside Kinetics & One Love, Alex da Kid, DJ Frank E, and Christine Dominguez. DJ Frank E also co-produced the song with Alex da Kid, Emily Boyle, and Sage Levy. The song was released to iTunes on April 13, 2010, and then to urban radio on April 27, 2010.

"Oh Santa!" is a song by American singer and songwriter Mariah Carey from her second Christmas album and thirteenth studio album, Merry Christmas II You (2010). Carey wrote and produced the song in collaboration with Jermaine Dupri and Bryan-Michael Cox. It was released as the lead single from the album on October 1, 2010 by Island Def Jam Records. It is an up-tempo R&B song about Carey making a plea for Santa Claus to bring back her partner in time for the Christmas holidays. It received a positive response from music critics, with many praising its composition and style.

"Tonight (I'm Fuckin' You)", censored as “Tonight (I'm Lovin' You)" or simply "Tonight" in altered versions, is a song by Spanish singer Enrique Iglesias. It features American rapper Ludacris and producer DJ Frank E. The song was released to US radio on 1 November 2010, as the album's second US single, and digitally on 22 November 2010. The altered version of the song was included on the French limited edition of Euphoria. The official remix features American rapper Pitbull.

"Right Now" is a song recorded by Barbadian singer Rihanna from her seventh studio album, Unapologetic (2012). The song features French disc jockey David Guetta. Rihanna co-wrote the song with R&B singers Ne-Yo and The-Dream, while their longtime collaborators, Norwegian production duo Stargate, co-produced the track alongside Guetta and his own longtime collaborators Nicky Romero and Giorgio Tuinfort. It was sent to contemporary hit and rhythmic contemporary radios in the United States as the fourth single from the album on May 28, 2013. Musically, "Right Now" is an EDM and pop song. The lyrical content features Rihanna chanting to live life in the moment.