"Yeah!" is a hip hop song by American singer Usher, written by American songwriters and producers Lil Jon, Sean Garrett, Patrick J. Que Smith, Ludacris, Robert McDowell and James Elbert "LRoc" Phillips. It was released as the lead single from Usher's hit fourth studio album, Confessions(2004). The track was produced by Lil Jon, who combined crunk and R&B in the song's beat. The song features vocals from Lil Jon and a rap verse from rapper Ludacris. This song could arguably be one of Usher (entertainer)'s most famous songs.

The song was remixed with Tego Calderón. It features a three-note beat that continues throughout the track. The song reached number 1 on twenty different charts in fifteen countries, and gained several platinum certifications, including by the RIAA and RIANZ. The single topped the U.S. Hot 100 for a record twelve weeks, the longest-running of 2004, and its huge success added to Usher's hit success that year. Usher was the longest-running number 1 artist in 2004 with four number 1 singles, and the most successful artist of 2004. With over two million worldwide sales in one year, it is one of the fastest selling hip hop songs ever. The song ranks 2nd on the BillboardHot 100 Songs of the Decade. Usher performed "Yeah!" at the Victoria's Secret Fashion Show 2008 as runway soundtrack. The song won Best Rap/Sung Collaboration at the 47th Grammy Awards.

In 2003, Usher submitted his fourth studio album, Confessions, to his label Arista Records, thinking it was already completed. However, when Usher and the company's then-president Antonio "LA" Reid listened to the songs, they felt the album needed a lead single. Although they had "Burn", the first song created early in the making of the album, as waiting list, Usher had to record a few more tracks.

Usher went back to the studio and enlisted fellow Atlantians rapper-producer Lil Jon, alongside rapper-actor Ludacris, to produce songs for him. Lil Jon recalled: "He needed a single. They had 'Burn,' 'Burn' was hot, but they needed that first powerful monster. That's when I came in."

Several months before Lil Jon came into the production of Confessions, he was commissioned by Jive Records to produce fifteen beats for rapper Mystikal. The rapper would only choose two tracks, which would give Lil Jon the chance to peddle the leftovers to other record labels. Without Lil Jon's knowledge, Jive Records gave one of the tracks that Mystikal passed on to hip hop artist Petey Pablo, who also records for the label. Lil Jon went to Pablo, who had already recorded the song, which later became "Freak-a-Leek". Lil Jon tried to settle it with Jive by making another beat for Pablo; however, Pablo did not give up the track, in light of the fact that it was already recorded and had been getting responses from South radio. Lil Jon comments, "With so much invested, Jive wouldn't give up the cut." Lil Jon reworked the track and a new instrumental was used, from which "Yeah!" was based. The song was co-written by Sean Garrett, Patrick J. Que Smith, Ludacris, Robert McDowell and James Elbert "LRoc" Phillips.

Though "Yeah!" had been created, the label was not ready to decide whether it would be released as the lead single, considering they had "Burn" on queue. Usher's friend and former A&R rep Kawan "KP" Prather commented: "'Burn' being a great song is one thing, but it's one of them things where people said, 'It's strong, but can we make history with that?' At the end of the day, you want an event." Usher was also skeptical if "Yeah!" was the right choice.

After Lil Jon leaked "Yeah!" to street DJs across the United States, Usher opted "Burn" as the lead single of the album and was already planning for its music video. The song was not intended to be a proper single and only a teaser for Usher's fans after waiting for years. However, the responses of "Yeah!" were overwhelmingly favorable, and "Yeah!" was released as the first single instead of "Burn", which became the second single from the album. The single was released in the United States on January 27, 2004 as a CD single and 12" single. In the United Kingdom, it was released as a CD single, containing the album and instrumental version of the song, and two unreleased tracks from the album, "Red Light" and "Sweet Lies".

"Yeah!" was lauded by contemporary critics for its production. Jem Aswad of Entertainment Weeklycalled it "irresistibly crunked-out", adding, "ensuing track glides smoothly between club-friendly hip-hop soul and ballads." Laura Sinagra Rolling Stonecommented that the song "creates sensual panic by combining Usher's jumpy attacks with Jon's sublime, frayed beats." Jon Caramanica of Blendernoted that "Yeah!" is the first song to mix "mainstream R&B and menacing Southern crunk." Sal Cinquemani of Slant Magazine said that the song has brought Usher to a "whole new level of crunk." Andy Kellman of Allmusic described the song as a "crunk-meets-R&B foundation" which features an "instantly addictive eight-note keyboard vamp". He added that because it is "absorbing", Ludacris' voice cannot be noticed that much. Matt Cibula of Popmatters characterized the song as a "full-fledged club über-crunk salacious" but he added that it fails to be a "club banger". Steve Jones of USA Todayreferred to "Yeah!" as a "club-rattling" song from a combination of "Atlanta's vibrant music scene", Lil Jon's "insistent beats" and Ludacris' "racy rhymes".

Critics complimented Usher for the song. Aswad called it the "grittiest song" Usher had sung for revealing his "newfound maturity". Caramanica said that it is "probably the scariest record — in a good way — he's ever made" and Usher "smartly shares the spotlight." Cibula stated that Usher's "smoove-ass" singing and Ludacris' presence contributes to the success of the single.

"Yeah!" was nominated at the 2005 Grammy Awards for Record of the Year, and won the Best Rap/Sung Collaboration award. At the 2005 Soul Train Music Awards, "Yeah!" was nominated for best R&B/Soul or Rap Dance Cut.

"Yeah!" charted well on various charts worldwide. The single debuted on the U.S. Hot 100 at number fifty-three on January 13, 2004, prior to its physical release. Seven weeks later, it peaked on the chart at number one on March 2, staying there for twelve consecutive weeks. "Yeah!" became Usher's fourth number-one single; Lil Jon's first; and Ludacris' second. The single remained on the Hot 100 for forty-five weeks. "Yeah!" became the most-played song in 2004. Nielsen Broadcast Data Systems placed the song on the top for getting 496,805 total plays, above Hoobastank's single "The Reason" with 489,976 spins. The single was certified platinum by the Recording Industry Association of America on June 11, 2006 for reaching one million shipments. "Yeah!" became the 2004's best-performing single in the United States. The single ranks at number 11 on The Billboard Hot 100 All-Time Top Songs.

Internationally, "Yeah!" received similar responses, topping many charts. The single reached number 1 in the Australia Singles Top 50, Austria Singles Top 75, Canadian Singles Chart, Denmark Singles Top 40, Dutch Top 40, France Singles Top 100, Germany Singles Top 100, Ireland Singles Top 50, New Zealand Top 40, Norway Singles Top 20, Swiss Singles Top 100, and the UK Singles Top 75. Overall, the single charted to different charts worldwide for a year, early in 2004 to early in 2005. The single was certified platinum by the Australian Recording Industry Association for selling 70,000 units. At the 2004 Year Ender charts, "Yeah!" became the twenty-eighth best-selling single in Australia. It was certified double platinum by the Recording Industry Association of New Zealand.

Mr. X, formerly Little X, had previously directed videos for Usher's singles "U Don't Have to Call" and "U Got It Bad". Mr. X said that the song reminded him of laser beams . He felt the sound was a laser beam for him, referring to the beat as "distinctive". Usher and Mr. X combined ideas to create a dance video for "Yeah!". The treatment was accompanied of how Usher wanted to be portrayed in the video, particularly showcasing his dance moves.

The music video was filmed in a vacant art gallery in Los Angeles over two days. When the shooting started, Mr. X recalled Michael Jackson's "low-tech" and "laser-flashing" 1979 "Rock With You" video, and used it as a reference. Forty extras were commissioned to dance with Usher, and two ladies to tempt him in different scenes. They went through photo browsing and phone calling, opting for Destiny, a friend of Mr. X, who seduces Usher in the club ala Marilyn Monroe wardrobe to complement the lyrics. Usher's other would-be seductress is portrayed by model Melyssa Ford. Lil Jon acted as an assistant director during the sessions. Usher took charge of his ideas on his wardrobe and choreography, with additional routines, specifically the Rockaway and the thunderclap, which Mr. X learned from Jamaica. The Rockaway influenced Fat Joe and Terror Squad's "Lean Back" video.

Usher's dancing in front of the green and blue laser beams is prominently featured throughout the video. Lil Jon and Ludacris appeared on the video as well. Ludacris protégé Chingy also appears near the end of the video, holding up his chain which shows his name. Sean "Diddy" Combs' former assistant, Farnsworth Bentley, made a cameo at the end of the video as well, when he was in Los Angeles and Mr. X begged him to dance in the video with his violin.

The music video debuted on MTV's Total Request Liveat number ten on February 19, 2004. "Yeah!" topped the countdown, and retired on May 3 at number six after appearing on the countdown for fifty days. "Yeah!" became one of the most successful music videos by Usher, alongside "Confessions Part II", which also remained for fifty days. At the 2005 Soul Train Music Awards, the video was nominated for Michael Jackson Award for best R&B/Soul or Rap Music Video.