Punk rock can be defined as an anti-establishment rock music movement with its origins in the United States and United Kingdom around 1974 or 1975, often exemplified by bands such as the Sex Pistols, The Ramones, Dead Kennedy's, and The Clash.
The term punk would be used to describe the associated culture, involving youthful aggression, ideologies, specific clothing styles, and a DO WHAT YOU WANT attitude. Historically the cities of London, New York City, Manchester, Detroit, Washington DC, and Los Angeles have been some of punk's breeding grounds.
Some Punk bands often will emulate the simple musical structures and arrangements of some 1960s garage punk rock bands. In 1976, the English punk fanzine Sideburns included drawings (later reproduced in Sniffin' Glue) of three chords, captioned: "This is a chord, this is another, this is a third. Now form a band". Most punk songs have a verse-chorus form and a 4/4 time signature. This emphasis on accessibility exemplified punk's DO WHAT YOU WANT aesthetic, and contrasted with the ostentatious musicianship of many mainstream rock bands popular in those years before the advent of punk. Back in the early days of punk rock, such musical virtuosity was looked on with suspicion - complicated guitar solos were considered unneccesary and self-indulgent, although simple guitar breaks was still very common, even in early punk songs.
Most Punk songs are usually about two and a half minutes long, and can be as short as 30 seconds to a minute. Punk rock usually will have faster tempos than most the rock bands who came before them. Typically, punk instrumentation includes a drum kit, one or two electric guitars, an electric bass guitar, and vocals. Drums typically sound loud, heavy, and dry, and often have a minimal set-up, with a (snare drum, one mounted or standing tom, one floor tom, one bass drum), hi-hats, one or two crash cymbals and a ride cymbal. Drum beats are usually simple, with quarter note grooves and not very technical bass or snare drum patterns. However, with hardcore punk the drumming is considerably faster and more technical. Most Bass lines are usually simple and consist only of the chords' root notes, although some modern punk bands - such as Rancid and Anti-Flag - put greater emphasis on more technical bass parts. Guitar parts usually include highly-distorted power chords, although some bands take a surf rock approach with a twangier guitar tones. Production is minimal, with tracks sometimes being laid down on home tape recorder.
The phrase punk rock (from punk, meaning a beginner or novice) was originally applied to the untutored guitar-and-vocals-based rock and roll of much United States bands of the mid-1960s such as The Standells, The Sonics, and The Seeds — bands that now would be categorized as garage rock.
Punk vocals may sometimes sound nasal, and are often shouted or screamed instead of sung in a conventional sense. In the mid-1970s, punk lyrics often involved much confrontational frankness and commentaries on social and political issues. Songs like The Clash's Career Opportunities and London's Burning dealt with unemployment, boredom, and other grim realities of urban life. Some songs were openly disparaging or against the political system, as in The Sex Pistols' God Save the Queen and Anarchy in the UK. Others were violent or anti-romantic in depictions of sex and love, such as The Voidoids' "Love Comes in Spurts".
Punk rock may have been influenced by the snotty attitude, on- and off-stage violence, and aggressive instrumentation, overt sexuality and political confrontation of artists like: The Who; Rolling Stones, Eddie Cochran, Gene Vincent and The Velvet Underground, Alice Cooper, The Stooges and MC5, Deviants; the New York Dolls. Other likely influences include the English pub rock scene, political UK underground acts such as Mick Farren, and British glam rock and art rock acts of the early 1970s, including David Bowie, Gary Glitter and Roxy Music. Influence from other musical genres, including reggae, funk, and rockabilly can also be detected in early punk rock.
The British punk movement may have drawn upon the do what you want attitude of the Skiffle music craze that emerged amid the post-World War II austerity in Britain. Punk rock in Britain coincided with the end of post-war consensus politics that preceded the rise of Thatcherism, and many British punk bands have expressed an angry attituded based on social alienation.
In December of 1976, the Sex Pistols, The Clash, The Damned, and Johnny Thunders & the Heartbreakers united for the Anarchy Tour, for a series of gigs throughout the UK. Many of these gigs were cancelled by the venue owners, after tabloid newspapers and other media seized on sensational stories regarding the antics of both the bands and their fans. The notoriety of punk rock in the UK was advanced by an infamous televised incident that was widely publicised in the tabloid press: on Thames Today, a London TV show, guitarist Steve Jones of the Sex Pistols was goaded into a verbal altercation by the host, Bill Grundy, swearing at him on live television in violation of then-accepted standards of propriety.
The United States saw this emergence of hardcore punk, which is known for fast, aggressive beats and political lyrics. Early hardcore bands include Dead Kennedys, Black Flag, Bad Brains, The Descendents, early Replacements, Bad Religion, and The Germs and the movement developed via Minor Threat, Minutemen and Hüsker Dü, among others. In New York, there was a large hardcore punk movement led by bands such as Agnostic Front, The Cro-Mags, Murphy's Law, Sick of it All, and Gorilla Biscuits. Though modern punk has shifted in different directions there is still a strong love for the music and the message it represents.
PUNKS NOT DEAD YET MOFUCKA!

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