Glam rock can be seen as a fashion as well as musical subgenre. Glam artists rejected the revolutionary rhetoric of the late 1960s rock scene, instead glorifying decadence, superficiality, and the simple structures of earlier pop music. Artists drew on such musical influences as bubblegum pop, the brash guitar riffs of hard rock, stomping rhythms, and 1950s rock and roll, filtering them through the recording innovations of the late 1960s. Ultimately it became very diverse, varying between the simple rock and roll revivalism of figures like Alvin Stardust to the complex art pop of Roxy Music. In its beginning, however, it was a youth-oriented reaction to the creeping dominance of progressive rock and concept albums – what Bomp! called the "overall denim dullness" of "a deadly boring, prematurely matured music scene".
Visually it was a mesh of various styles, ranging from 1930s Hollywood glamour, through 1950s pin-up sex appeal, pre-war cabaret theatrics, Victorian literary and symbolist styles, science fiction, to ancient and occult mysticism and mythology; manifesting itself in outrageous clothes, makeup, hairstyles, and platform-soled boots. Glam is most noted for its sexual and gender ambiguity and representations of androgyny, beside extensive use of theatrics.
It was prefigured by the flamboyant English composer Noël Coward, especially his 1931 song "Mad Dogs and Englishmen", with music writer Daryl Easlea stating, "Noël Coward's influence on people like Bowie, Roxy Music and Cockney Rebel was absolutely immense. It suggested style, artifice and surface were equally as important as depth and substance. Time magazine noted Coward's 'sense of personal style, a combination of cheek and chic, pose and poise'. It reads like a glam manifesto." Showmanship and gender identity manipulation acts included the Cockettes and Alice Cooper, the latter of which combined glam with shock rock.