"American Girl" is the second single from Tom Petty and the Heartbreakers' self-titled debut album. The single did not chart in the U.S. (until it was re-released in 1994, it only managed to peak at nine in Bubbling Under Hot 100 Singles though), but in the UK it peaked at #40 the week ending August 27, 1977. The song was ranked 76th on the list of "The 100 Greatest Guitar Songs of All Time" by Rolling Stone.

"American Girl" uses standard rock instrumentation of electric guitars (Petty and Campbell), electric bass (Blair), drums (Lynch), and keyboards (Tench). The tempo is fast and "urgent", and is built on a repeated jangling guitar riff based on a "Bo Diddley beat".

As described in Rolling Stone, "The supercharged riff set the template for decades of Petty hits, but it was also an homage to the Byrds: Petty and Mike Campbell's twin guitars mirrored Roger McGuinn's 12-string, infusing the folk-rock sounds of the 1960s with New Wave energy."

Due to the lyrics about a desperate girl on a balcony hearing "cars roll by out on 441", the song was rumored to have been written about a college student who committed suicide by jumping from the Beaty Towers residence hall at the University of Florida in Gainesville, Florida. Beaty Towers is located on the edge of the university campus alongside U.S. Route 441 (called NW 13th Street through the city), and the residence hall opened in 1967, when Petty was still a teenager living in his hometown of Gainesville.

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