John Legend is among the best crooners of this generation. Starting as a collaborator for other artists, he launched his own solo music career with the 2004 album "Get Lifted." He is behind the popular songs "Ordinary People," "Save Room," and "All of Me."

John Legend
(Photo : Wikimedia Commons)

As a testament to his talents, Legend is among the only fifteen people to have won all four major awards: Emmy, Grammy, Oscar, and Tony. Aside from writing and performing his hits, the Legend has also written songs for other artists. Here are five popular songs John Legend wrote for other artists you probably didn't know:

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"American Boy" by Estelle, featuring Kanye West (2008)

This hit from the British rapper-singer Estelle appeared in her second album "Shine," featuring Kanye West. However, this popular song was also co-written by John Legend, together with Estelle, West,, John Stephens, and more.

It brought Estelle mainstream success in many countries as it reached Top 5 in most countries in Europe and Oceania, as well as her native UK. In the US, it reached the No. 9 spot on the Billboard Hot 100, marking her breakthrough in this market.

"Finally" by Fergie (2008)

One of the popular songs from Fergie's debut album was co-written by John Legend, with Fergie and Stefanie Ridel. It was a surprising, yet welcome, addition to the former Black Eyed Peas' vocalist's music. The power ballad, reminiscent of Broadway performances, narrates her own journey.

For a song that never got its own music video released, "Finally" peaked at the Billboard's Bubbling Under Hot 100 Singles. It also charted in the Mainstream Top 30, Pop 100, and the Canadian singles chart. Both Fergie and Legend performed the song together at the Idol Gives Back even in 2008. The duo also sang "Finally" during the 50th Grammy Awards.

"I Want You" by Janet Jackson (2004)

The year 2004 shadowed Janet Jackson's career because of the infamous Super Bowl Halftime Show controversy. In the incident, Jackson was unintentionally partly undressed by Justin Timberlake during their performance. It led to the blacklisting of her music videos and singles worldwide.

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However, this popular song, co-written by John Legend and Kanye West, among others, managed to receive generally positive reviews at the time of controversy. Before it was taken off the air as a part of the penalty, it also peaked at No. 18 on the Hot R&B/ Hip-Hop Songs Charts. "I Want You" also peaked at No. 4 at the Urban Adult Contemporary Chart.

"Listen" by David Guetta, featuring John Legend (2016)

The carrier single from David Guetta's sixth studio album features Legend providing the song's vocals. Aside from Guetta, a number of other songwriters pitched in the development of the song, with John Legend receiving co-writing credits. In an attempt to break free from conventional EDM sounds, David Guetta started collaborating with other artists to work on incorporating different genres into his album. 

Unfortunately, the album received mixed reviews, with other critics noting how Guetta appeared as the featured artist in his own record. "Listen" was one of those songs, with Legend's croons overshadowing Guetta's beats.

To read more about your favorite singers writing songs for other artists, check out:  

6 Popular Songs Ed Sheeran Wrote For Other Artists [You Probably Didn't Know],

6 Songs You Didn't Know Bruno Mars Worked On,

5 Hit Songs Taylor Swift Wrote [That You Probably Didn't Know]