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Punk rock (also known as simply punk) is a music genre that emerged in the mid-1970s. Rooted in 1950s rock and roll and 1960s garage rock, punk bands rejected the corporate nature of mainstream 1970s rock music. They typically produced short, fast-paced songs with hard-edged melodies and singing styles with stripped-down instrumentation. Lyricism in punk typically revolves around anti-establishment and anti-authoritarian themes. Punk embraces a DIY ethic; many bands self-produce recordings and distribute them through independent labels.

The term "punk rock" was previously used by American rock critics in the early 1970s to describe the mid-1960s garage bands. Certain late 1960s and early 1970s Detroit acts, such as MC5 and Iggy and the Stooges, and other bands from elsewhere created out-of-the-mainstream music that became highly influential on what was to come. Glam rock in the UK and the New York Dolls from New York have also been cited as key influences. Between 1974 and 1976, when the genre that became known as punk was developing, prominent acts included Television, Patti Smith, and the Ramones in New York City; the Saints in Brisbane; the Sex Pistols, the Clash, and the Damned in London, and the Buzzcocks in Manchester. By late 1976, punk had become a major cultural phenomenon in the UK. It gave rise to a punk subculture that expressed youthful rebellion through distinctive styles of clothing, such as T-shirts with deliberately offensive graphics, leather jackets, studded or spiked bands and jewelry, safety pins, and bondage and S&M clothes.

In 1977, the influence of the music and subculture spread worldwide. It took root in a wide range of local scenes that often rejected affiliation with the mainstream. In the late 1970s, punk experienced a second wave, when new acts that had not been active during its formative years adopted the style. By the early 1980s, faster and more aggressive subgenres, such as hardcore punk (e.g., Minor Threat), Oi! (e.g., Sham 69), street punk (e.g., the Exploited), and anarcho-punk (e.g., Crass), became some of the predominant modes of punk rock, while bands more similar in form to the first wave (e.g., X, the Adicts) also flourished. Many musicians who identified with punk or were inspired by it went on to pursue other musical directions, giving rise to movements such as post-punk, new wave, thrash metal, and alternative rock. Following alternative rock's mainstream breakthrough in the 1990s with Nirvana, punk rock saw renewed major-label interest and mainstream appeal exemplified by the rise of the California bands Green Day, Social Distortion, Rancid, the Offspring, Bad Religion, and NOFX.