Heavy metal is a loud, aggressive style of rock music characterized by strong rhythms, guitars, bass, and drums. The term was first used by music critic Lester Bangs in the 1970s to describe bands like Steppenwolf. Metallica and Slipknot are two famous heavy metal bands. Formed in the 1980s, Metallica drew on punk and British metal styles and helped define the genre. Slipknot, formed in 1995, rose to fame with their self-titled debut album in 1999 and are known for their unique musical style and masks. The article argues that people should not judge other musicians' styles and genres, as music allows expression in different ways.