Related styles

Hard rock is closely related to heavy metal (and often the terms overlap in usage), but it does not always match the description of what purists consider the definition of heavy metal. While still guitar-driven in nature and usually riff-based, its themes and execution differ from that of the major heavy metal bands listed earlier in this article. This is perhaps best exemplified by The Who in the late-1960s and early-1970s, as well as other 1970s and 1980s bands like Queen who have had a large influence on heavy metal music, AC/DC, Aerosmith, Kiss, Thin Lizzy, and Scorpions.

Glam rock (or glitter rock) - a short-lived era in the early 1970s, relied on heavy, crunchy guitars, anthemic songs, and a theatrical image. T. Rex, David Bowie (particularly in his incarnation as Ziggy Stardust) and Alice Cooper are among the more popular standard examples of this sub-genre. Some cross-influence has occurred between punk rock and heavy metal (especially NWOBHM). An example is Motörhead; the band's leader Lemmy, spent time in punk band The Damned and attempted to teach Sid Vicious how to play bass guitar. Alternative rock, particularly grunge, sometimes takes influence from heavy metal. Some grunge bands such as Soundgarden and Alice in Chains were marketed as metal before alternative became a viable commercial force.