Interpolation refers to using a melody — or portions of a melody (sometimes with modified lyrics) — from a previously recorded song but re-recording the melody instead of sampling it. Interpolation is often used when the artist or label who owns the piece of music declines to license the sample, or if licensing the piece of music is considered too costly. One genre where interpolating (as well as sampling) is highly prevalent is hip hop music; an example is Sting's "Shape of My Heart" interpolated in Juice WRLD's 2018 hit "Lucid Dreams". Another example is "Bad Liar" by Selena Gomez which interpolates the bass line of "Psycho Killer" by the band Talking Heads. An interpolated work is a composition that takes portions of an existing source (e.g., recording) and uses that melody or portions of a melody within that new work.
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