Straight edge is a punk subculture that started in the 1980s. People in this movement swear off alcohol, tobacco, and drugs. Some also avoid meat and casual sex. They adopted the name from a song by the band Minor Threat. The idea came from punk's energy but reacted against its perceived excesses. It's all about self-control and rejecting mainstream influences. Hardcore punk music was a big part of it from the start.
The movement has gone through different phases over time. In the 1990s, it became more political, with some groups focusing on animal rights or even violence. Other groups, like "bent edge," pushed back against the strict rules. Straight edge spread far beyond America, reaching Europe and other parts of the world. Today, many straight edge people are peaceful, though some still hold strong views. The music keeps changing, but the core idea of staying clean remains.