"i" is a song by American rapper Kendrick Lamar. It was released on September 23, 2014 as the lead single from Lamar's third studio album To Pimp a Butterfly. The song utilizes music from "That Lady", written by and originally performed by R&B group The Isley Brothers, elements from which were re-recorded rather than being directly sampled from the original record. "i" won two awards at the 2015 Grammy Awards: Best Rap Performance and Best Rap Song.

"i" was produced by Los Angeles producer Rahki, who also produced the song "Institutionalized". Although the version of "i" that appears on the album is drastically different from the single release, both versions contain a sample of the song "That Lady" by The Isley Brothers. Lamar personally visited Isley Brothers' lead vocalist Ronald Isley to ask his permission to sample the song: "I actually had to go to St. Louis and get the blessings from Ronald Isley," he said. "That was a trip. We got in the studio and just vibed and talked about how things were back then and how they are now, and you can actually hear him on the record with a few ad-libs that he actually did. We got it on camera and things like that, it’s a beautiful thing." Isley also performs on the song "How Much a Dollar Cost?" with singer-songwriter James Fauntleroy.

The single cover for "i" features members of gangs the Bloods and the Crips forming a heart, on the subject of the cover art Lamar said in an interview with AMP Radio: "Where I'm from, there's a lot of gang culture and things like that, so instead of throwing on up gang signs, which we used to, I put a Blood and I put a Crip together and we’re throwing up hearts...sparking the idea of some type of change through music or through me because I go back to the city now and people give me the honor and respect that, you know, this kid can change a little bit something different that’s been going on in the community."

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