Hybrid Theory is the debut album by American rock band Linkin Park. Recorded at NRG Recordings in North Hollywood, California, and produced by Don Gilmore, the album's lyrical themes deal with problems lead vocalist Chester Bennington experienced during his adolescence, including drug abuse and the constant fighting and divorce of his parents.

Hybrid Theory takes it's title from the previous name of the band as well as the concept of music theory and combining different styles. Four singles were released from the album: "One Step Closer", "Crawling", "Papercut", and "In the End", all of them responsible for launching Linkin Park into mainstream popularity. At the 2002 Grammy Awards, Hybrid Theory was nominated for Best Rock Album.