In case you haven't checked out the wiki on punk lately:
Punk rock is a rock music genre that developed between 1974 and 1976 in the United Kingdom, United States, and Australia. Rooted in garage rock and other forms of what is now known as protopunk music, punk rock bands eschewed perceived excesses of mainstream 1970s rock. Punk bands created fast, hard-edged music, typically with short songs, stripped-down instrumentation, and often political, anti-establishment lyrics. Punk embraces a DIY ethic; many bands self-produced recordings and distributed them through informal channels.
The term "punk" was first used in relation to rock music by some American critics in the early 1970s, to describe garage bands and their devotees. By late 1976, bands such as the Sex Pistols, The Clash and The Damned in London and Television and the Ramones in New York City were recognized as the vanguard of a new musical movement. The following year saw punk rock spreading around the world, and it became a major cultural phenomenon in the United Kingdom. For the most part, punk took root in local scenes that tended to reject association with the mainstream. An associated punk subcultureemerged, expressing youthful rebellion and characterized by distinctive styles of clothing and adornment and a variety of anti-authoritarian ideologies.