Heavy metal may be the most widely misunderstood form of music in Western culture, and its identity has grown increasingly obscure over the past four decades as fans, journalists, and musicians have continued calling new and more divergent stylistic evolutions by the same name. The result is the all-too-familiar experience for fans of metal music to strike up a conversation with each other only to discover that they share no common interests in music.
Despite the frequent use of "metal" and "heavy metal" as interchangeable terms, it's relevant and accurate to think of them as their own categories of music. Fortunately, the difference between them is easy to understand by looking back over the history of heavy metal.
Dio - "Stand Up and Shout" (1983)
Note: The formation and naming of new genres is always a messy process and much easier to parse with hindsight, and so this article benefits from a broad historical perspective as well as access to virtually all recorded music – advantages that fans, musicians, and journalists did not have in heavy metal's early days.
This article is also rooted in a firm belief that genre classifications are an essential part of music appreciation and have the potential to greatly enhance our enjoyment of music.
This overview of heavy metal is meant to be a flexible way of discussing prominent evolutions of the music while acknowledging that all genres are inherently valuable and worth recognizing with terms that respect their individual identities.
What Is Heavy Metal?
All of the confusion around the name "heavy metal" stems from the fact that heavy metal is the original form of metal music. From a historical perspective, it makes considerably more sense to think of heavy metal as a specific subgenre of metal music than a synonym for the entire metal genre.
As a subgenre, heavy metal functions in precisely the same way as thrash metal, black metal, power metal, or any other evolution of the style.
All of the confusion around the name "heavy metal" stems from the fact that heavy metal is the original form of metal music.
This confusion is understandable. As heavy metal evolved into new forms such as power metal and thrash metal, it became common for fans, musicians, journalists, and record labels to simply continue calling all of it "heavy metal." (This is far from a unique phenomenon, and it is observable in a wide variety of popular music genres.)
Despite the convenience of using the original moniker for all music that followed, doing so has made it difficult for many to perceive or remember that "heavy metal" has its own specific identity within the larger metal family, and a massive and vibrant form of music has been obscured in the process.
For that reason, it's worth taking a step back and identifying some key characteristics of metal music's foundational form.
Riot - "Heavy Metal Machine" (1983)
Heavy metal is played almost exclusively with drums, electric guitars, and electric bass guitar, though synthesizers and acoustic guitars are historically prevalent accompaniments as well. Heavy metal is often associated with soaring, clean vocals, most famously from Rob Halford and Bruce Dickinson, though numerous examples of singers with coarse deliveries – such as Udo Dirkschneider – exist as well.
Heavy metal exhibits prominent elements of ‘70s hard rock in its foundation, though it is generally faster and more aggressive in its delivery. The style also features greater guitar distortion and leans on steely production for its gritty character. Many hard rock bands of the '70s – such as Riot, Saxon, and Judas Priest – made the shift into the more aggressive heavy metal sound in the early '80s, and their discographies represent the rapid and steady evolution of the new style.
Somewhat ironically, heavy metal is melodic, and on a structural level, is a form of pop music. Songs typically follow an ABABCBB format in which A is the verse, B is the chorus, and C is the bridge – almost always a guitar solo. Like pop music, the songs feature memorable chorus hooks and prominent, recurring instrumental melodies.
Somewhat ironically, heavy metal is melodic, and on a structural level, is a form of pop music.
In addition to well-known ‘80s releases from Black Sabbath, Judas Priest, and Iron Maiden (more on these bands later), examples of music at the very heart of true heavy metal include Dio’s Holy Diver and Accept’s Balls to the Wall, both from 1983.
Armored Saint’s March of the Saint (1984) and Savatage’s Power of the Night (1985) are similarly excellent examples of heavy metal, even though those bands later evolved into American power metal and a more progressive style of heavy metal, respectively.
Armored Saint - "Can U Deliver" (1984)
In order to understand heavy metal in a broader context, it’s useful to recognize the rich spectrum of creative styles radiating outward from the subgenre to its nearest musical neighbors. This blending of styles is natural and evident across all forms of music, and it helps to explain how the name "heavy metal" continued to be passed along to new styles of music, including ones that eventually held no relationship to the heavy metal sound.
For example, it’s entirely possible to line up songs or albums to form a continuous musical spectrum from heavy metal into speed metal, then power metal, thrash metal, and death metal in such a way that the differences are unnoticeable between individual songs but become dramatic as a person listens across dozens or hundreds of creations.
Among metal subgenres, arguably the greatest gray area around heavy metal exists with its neighbors in speed metal and early power metal. Because many speed metal and early power metal releases from the 1980s (and more recently from the NWOTHM revival) display relatively small evolutions of the heavy metal sound, they can often be classified within the boundaries of traditional heavy metal.
Accept's "Fast as a Shark" is an excellent example of a speed metal track that is also fully classifiable as heavy metal.
Accept - "Fast as a Shark" (1982)
It's similarly worth noting that early releases from progressive metal bands like Fates Warning and Queensrÿche fall within the scope of heavy metal, even though they often feature more complex songwriting and arrangements than their counterparts.
Heavy metal also overlaps significantly with doom and thrash, as well as the high-speed sounds of European power metal that emerged in the late '80s. There is also a small but historically significant connection between heavy metal and black metal.
Because of the amount of creative overlap across related styles, many albums can be classified within multiple metal subgenres or described with hybrid terms. A perfect example of this is Sanctuary’s 1988 album Refuge Denied, which can be considered a heavy metal album but pulls strong influences from thrash metal and American power metal.
Sanctuary - "Die for My Sins" (1988)
It's also impossible to ignore the close, inextricable relationship between heavy metal and its older musical sibling, hard rock. Although the vast majority of hard rock and heavy metal creations can be cleanly placed into one camp or the other, the space between the two has maintained a healthy gray area from the late ‘70s into the present. (Bullet is an excellent example of a modern band that lives in both worlds.)
Despite all of these notable blurred edges, however, there remains an enormous volume of music in the world that falls squarely within the heavy metal subgenre and can be classified simply as "heavy metal." Listening to large quantities of music in the style – hundreds or even thousands of albums – makes it easy to identify the overall shape of the subgenre as well as the boundaries where it begins to blend into other styles.
Because of the amount of creative overlap across related styles, many albums can be classified within multiple metal subgenres or described with hybrid terms.
Terms like "traditional heavy metal" and "true heavy metal," are useful names for describing bands that play nearer to the center of the heavy metal subgenre than acts with a hybrid or evolved sound. This is often relevant even within a single band’s discography. For example, Black Sabbath’s Mob Rules (1981) can be safely classified as a traditional heavy metal album, while their later recording 13 (2013) is a blend of heavy metal and doom metal.
Similarly, Armored Saint’s 1984 album March of the Saint is a traditional heavy metal album, while the band's 1991 release Symbol of Salvation falls more within the scope of American power metal. It’s not inaccurate to call these bands’ later releases “heavy metal,” but they exist outside the nucleus of the style.
As naming conventions, "traditional heavy metal" and “true heavy metal” are also relevant for fans who want to talk more specifically about the bands they enjoy and distinguish them from acts like Korn, Slipknot, or Rammstein that helped pioneer later forms of music that exist outside the scope of heavy metal.
Queensryche - "Warning" (1984)
Equally important to the understanding of what is heavy metal is a discussion of what is not heavy metal.
Heavy metal does not contain operas, neoclassical songwriting and guitar work, symphonies, or a synthesizer’s approximation of symphonies.
Unlike nu metal and other, newer forms of music, heavy metal does not feature Latin rhythms or South American folk instruments, nor does it not employ any type of music sampling or turntables.
It does not include industrial rhythms, EDM beats, or other strong use of synthesizers.
Heavy metal does not use hip-hop vocal deliveries, nor does it include harsh screams and guttural growls like the kinds found in death metal, black metal, and some thrash metal.
Labels like “symphonic heavy metal” and “electronic heavy metal” are contradictions in terms, and most bands in those categories deserve better and more original genre labels for their diverse sounds and willingness to explore fresh musical ideas.
The majority of heavy metal albums were released between 1980 and 1992, though the style has seen a significant revival since 2008 with the new wave of traditional heavy metal (NWOTHM). The years in-between those periods saw very few traditional heavy metal albums. If there are any doubts about recordings from the ‘90s and ‘00s, it is safe to assume they are not part of the heavy metal subgenre.
Ambush - "Heading East" (2014)
To briefly summarize, "metal" can be thought of as a broad genre of music with dozens of subgenres, while "heavy metal" is a specific subgenre within that broader category. Again, it's useful to think of this in the same way as thrash metal or death metal.
"Metal" can be thought of as a broad genre of music with dozens of subgenres, while "heavy metal" is a specific subgenre within that broader category.
Just as it would be confusing to refer to all metal music as "thrash metal," it complicates conversations and obscures understanding of the original form of metal music to use the term “heavy metal” as a general and all-encompassing term for everything that came after it.
The History of Heavy Metal
In order to more fully appreciate the characteristic sounds of heavy metal, it's worth exploring the early history of the metal genre and its relationship with rock music, particularly the years from 1970 to 1980.
Note: Before diving into heavy metal's genesis, it's worth emphasizing that music genres shift rapidly when they are new and grow increasingly rigid over time as a greater volume of music is created in and around them.
For example, if only a dozen albums exist within a certain style, it's difficult to give that style a name or fully recognize the shape of that genre in relation to its nearest musical neighbors. However, by the time several hundred or even several thousand albums exist within that style, the shape of that genre and the places where its edges blend into related styles becomes easily identifiable.
With that in mind, the following discussion pulls context from thousands of rock and metal creations across decades of stylistic evolutions.
Since the point in question is the name “heavy metal” and its usage, it’s helpful to start with the etymology of the term as it applies to music. In the late ‘60s, the words “heavy,” and very occasionally, “heavy metal,” began to be tossed around in song lyrics and descriptions of music, especially in hard rock. When Black Sabbath’s 1970 self-titled debut was released, it became a magnet for the terms due to the band’s uniquely ponderous sound.
The newness of Sabbath’s playing style and the still very loose application of the words “heavy” and “heavy metal” caused writers and fans to commonly use them interchangeably with “rock” and “hard rock” to describe music throughout the ‘70s. From a historical perspective, this proves to be a justifiable bit of ambiguity, especially as the majority of Sabbath’s songs, especially those released between 1973 and 1978, fell much closer to acid rock and bluesy hard rock than the heavy metal style that emerged later.
Saying that Black Sabbath was the first metal band is a massive oversimplification of the various evolutions of the group and their music, as well as their role in the development of the metal genre.
Most other ‘70s bands saddled with the “heavy metal” tag were even closer stylistically to the heart of rock music than Sabbath was. For example, Led Zeppelin had a milder, bluesier sound with prominent elements of folk music, Deep Purple had a feel-good roadhouse rock vibe that was often too light to even be classified as hard rock, and Aerosmith played a strong mix of blues and hard rock that was an immediate evolution of ‘60s rock acts like The Rolling Stones.
Although these bands were each making significant contributions to music history, their styles fall within the scope of rock and hard rock and therefore need no new genre names to classify them.
In contrast with their contemporaries, it’s clear that Black Sabbath pioneered a new approach to songwriting and production in the ‘70s, one that ultimately laid the foundation for the metal genre. However, saying that Black Sabbath was the first metal band is a massive oversimplification of the various evolutions of the group and their music, as well as their role in the development of the metal genre.
Prior to 1969, Black Sabbath played a brand of bluesy hard rock with a deeply distorted guitar sound under the band name Earth, and before that as an even less rock-oriented incarnation as the Polka Tulk Blues Band.
In 1969, the band overhauled their sound, as well as their conceptual themes, under the Black Sabbath moniker, choosing to focus on heavy distortion and the grinding, leaden playing style they had recently developed.
Notably, the pioneering new sound heard on Sabbath’s first four albums — Black Sabbath (1970), Paranoid (1970), Master of Reality (1971), and Vol. 4 (1972) — turned out to be much more formative to doom metal than to heavy metal.
The achingly downtempo, trudging delivery of tracks like “Black Sabbath” and “Electric Funeral” bear virtually no resemblance to the heavy metal creations that emerged a decade later, including those from Black Sabbath themselves.
Black Sabbath - "Electric Funeral" (1970)
However, their influence can be heard prominently in the songs of ‘80s doom acts Pentagram and Candlemass, for example on Pentagram’s “When the Screams Come.” The sounds of those early Black Sabbath creations can also be clearly perceived in the death-doom of early-‘90s Paradise Lost songs like “Rotting Misery” and “The Painless” along with countless other doom metal creations.
Not coincidentally, the massive resurgence of doom rock, doom metal, and stoner rock of the 21st century has brought prominent elements of the blues along with it. This music often aligns directly with those earliest Black Sabbath albums, and it is noticeably distinct in its creative approach from the more energetic and clear-headed sounds of heavy metal that flourished throughout the 1980s as well as that music's revival in NWOTHM.
Sabbath’s next two releases of the decade, Sabbath Bloody Sabbath (1973) and Sabotage (1975), notably backed off the group’s signature gloomy style for a more fanciful, acid-washed rock sound with experimental use of synthesizers and protracted, jam-style instrumental sections.
Black Sabbath continued the decade with an even greater shift away from their signature sound, delivering playful, Beatles-esque rock music on Technical Ecstasy (1976) that was almost unrecognizable from the band's debut. Never Say Die! (1978) revived some of Sabbath’s heaviness, though the music frequently fell into soft, dreamy spaces and was missing much of the attitude and energy of other rock albums from the same year.
The pioneering sound heard on Sabbath’s first four albums turned out to be much more formative to doom metal than to heavy metal.
This move away from Sabbath’s trademark heavy sound complicated discussions about heavy metal and led to an understandable jump in logic: if Black Sabbath was considered a heavy metal band, yet played lighthearted rock music like “Looking for Today” and “A Hard Road,” then bands like Deep Purple and Heart should be classified as heavy metal as well.
However, despite the ambiguity, heavy metal was actually moving much closer to a clear identity and definition thanks to innovative releases from other bands in the late '70s.
Rainbow and Judas Priest
As Black Sabbath shifted away from their early identity, a handful of other bands picked up where they left off and began paving the way toward a more established and recognizable heavy metal genre. These creators played a somewhat different style of music from Sabbath’s doom rock, and their releases in the second half of the ‘70s were much more immediate and direct precursors to true heavy metal.
Foremost among these acts are Rainbow and Judas Priest.
Rainbow - "Kill the King" (1978)
Rainbow’s Rising (1976) and Long Live Rock ‘n’ Roll (1978), as well as Judas Priest’s final two releases of the decade, Stained Class (1978) and Killing Machine (1978) – the latter re-released as Hell Bent for Leather – pointed the way to an exciting and innovative new sound.
Although these albums can primarily be classified as hard rock, they focused on tighter, more aggressive playing styles and more energetic songwriting than almost all hard rock that had come before them – including Sabbath’s '70s releases.
It's also worth noting that these albums contained significant stylistic evolutions within Judas Priest and Rainbow's own discographies, as they embraced a more upbeat, rollicking sound driven by power chords, invigorating guitar solos, and catchy vocal hooks, all packed into accessible pop song structures.
Other significant efforts from the late ‘70s featuring this new sound include Scorpions’ 1979 album Lovedrive and Saxon’s self-titled debut from the same year, both of which exist on the fringes of hard rock where the genre blends into heavy metal.
Incidentally, with the exception of Judas Priest, each of these heavy metal pioneers would shift back into lighter, hard rock sounds in the ‘80s, effectively turning over the job of constructing heavy metal once again to other artists.
Although the term “heavy metal” had been in use for over a decade, it never had a consistent or concrete musical style to attach itself to, and the term remained relatively undefined throughout the ‘70s.
However, the seeds of heavy metal, first planted by Black Sabbath and nurtured by acts like Rainbow and Judas Priest, were on the verge of sprouting into the first true heavy metal creations.
The Birth of Heavy Metal
1980 is the critical year in heavy metal’s evolution, when the ideas percolating around the music coalesced and solidified into an undeniably new sound. This effort was spearheaded by three seminal recordings: Black Sabbath’s Heaven and Hell, Judas Priest’s British Steel, and Iron Maiden’s Iron Maiden. These recordings established a bold new style that further hacked away at heavy metal’s hard rock roots and fully severed ties with the blues.
Judas Priest - "Rapid Fire" (1980)
1980 also saw a small number of releases that contained a mixed collection of this new heavy metal sound alongside the earlier sounds of hard rock. Two notable examples in this group are Saxon’s Strong Arm of the Law and Accept’s I’m a Rebel.
More significantly, each of the 1980 albums from Sabbath, Priest, and Maiden embarked on a new trajectory of music and established a bold precedent for bands to follow.
Black Sabbath had recently fired Ozzy Osbourne and set out to redefine themselves with a new singer in Rainbow’s Ronnie James Dio. The revamped sound that emerged on Heaven and Hell was strikingly different from the loose, softhearted rock on the band’s last two albums and nearly as different from the rest of their discography.
Where Ozzy droned, Dio soared, and Heaven and Hell displayed an element of imagination and mysticism rarely heard from the band previously. It borrowed heavily from Rainbow’s musical delivery and took note of the pop appeal of rising commercial rock acts like Van Halen. The new songwriting was cleaner, tighter, faster, and significantly more deliberate than before. Notably, the production was also heavier and crunchier than on albums from Rainbow and other hard rock acts of the ‘70s.
Where Ozzy droned, Dio soared, and Heaven and Hell displayed an element of imagination and mysticism rarely heard from the band previously.
Fluid, uptempo tracks like “Neon Knights” and “Die Young” remain archetypal examples of true heavy metal.
Black Sabbath - "Neon Knights" (1980)
Judas Priest similarly unveiled a new sound in 1980. The band had steadily shifted away from the romantic, occasionally progressive rock sound of mid-‘70s releases Rocka Rolla and Sad Wings of Destiny to forge a new and heavier style of music with each release throughout the ‘70s. This pattern of evolution brought them to the grounded and rough-hewn song structures of the impossibly influential British Steel.
It was the most aggressive recording from Judas Priest to date, with tracks like “Rapid Fire” and “Steeler” kicking up the tempo and sonic power of the music beyond anything the band had done before.
To accent the energetic new songwriting, British Steel‘s production became thicker and more rugged than on Stained Class and Hell Bent for Leather, delivering dynamic percussion, hard-hitting rhythm guitars, and screaming guitar solos that remain the exemplary sound of heavy metal.
British Steel was the most aggressive recording from Judas Priest to date, with tracks like “Rapid Fire” and “Steeler” kicking up the tempo and aggression beyond anything the band had done before.
Iron Maiden, the youngest band of the three, and the only one without a formal release to their name, unquestionably brought with them the most energy and speed, quickly attracting a following from disenchanted fans roaming a fractured British punk music scene. Of the three pivotal contributions made in 1980, Iron Maiden’s self-titled debut had the lightest overall sound, though the energy, attitude, and melodic sensibilities of the music was frequently far removed from hard rock and contained no traces of the blues.
It was not until Iron Maiden's 1982 release, The Number of the Beast, that the group would cement themselves as a heavy metal band in the full sense of the term, though their first two recordings remain pivotal creations at the dawn of the new musical style.
The bold sound of Heaven and Hell, British Steel, and Iron Maiden, along with their immediate follow-ups from all three bands in 1981, helped ignite a rapid proliferation of heavy metal music.
Although the name “heavy metal” had continued to be loosely attributed to British hard rock acts like Def Leppard, Whitesnake, and AC/DC, an unmistakable demarcation line had been established in 1980.
As hundreds of bands emulated these recordings in the coming decade, the shape and name of heavy metal gained clarity and substance and became undeniably distinct from the rock and hard rock recordings that preceded them.
Some of these artists, like Armored Saint, Savatage, and Queensrÿche, signed to major record labels and produced polished recordings with commercial appeal. Many more released their records independently or through small labels, opting for gritty production with harsh, dungeon-like sound quality.
Blacksmith - "Louder Than Hell" (1989)
In many cases, these unrecognized bands recorded just one or two albums before disbanding or moving on to more profitable music endeavors. Along with lesser-known artists who blended their sound with emerging styles like thrash and speed metal, these bands collectively form the ironclad, uncompromising sound of ‘80s underground metal that remains the primordial soup and spiritual heart of all metal music.
The Metal Explosion
As heavy metal flourished over the next few years, it began to evolve rapidly at the edges, creating strikingly new forms of music. However, because the splinter styles were fundamentally rooted in heavy metal, they adopted similar names: thrash metal, death metal, power metal, etc.
Each year of the ‘80s introduced music with more aggressive, more technical, and more extreme sounds, and suddenly the term “heavy metal” that loosely applied to early outgrowths of the style was no longer relevant to a significant number of new bands.
An example of this rapid evolution, and the confusion that accompanied it, comes in the form of Slayer’s early recordings.
It was not inconceivable at the time to classify Slayer’s 1983 debut Show No Mercy as heavy metal. After all, the more extreme metal outgrowths were still in their infancy, and Tom Araya’s high-pitched wails and the group’s articulate riffing and rhythms still held notable similarities to the earliest heavy metal recordings.
Slayer - "The Antichrist" (1983)
With few other creations to compare it to, Slayer's Show No Mercy often and understandably received the heavy metal label. However, by 1986, and the raucous, frenetic style exhibited on Reign in Blood, the term could've easily been dropped in favor of the emerging "thrash metal" label. Yet despite the fact that Slayer was clearly pioneering a bold new sound, they often continued to be included under the "heavy metal" banner.
Suddenly the term “heavy metal” that loosely applied to early outgrowths of the style was no longer relevant to a significant number of new bands.
By 1990, the metal genre had expanded to include music that exhibited even more dramatic evolutions of those pivotal 1980 releases, such as Morbid Angel’s Altars of Madness and Megadeth’s Rust in Peace. It became increasingly common to refer to the music collectively as simply “metal.”
This made sense, as all the subgenres of the newly expanded metal genre had their respective adjectives. However, the term “heavy metal” continued to be used redundantly for all outgrowths of the original style despite the fact it only applied to the songwriting approach of a slice of the now immense and immensely popular metal genre.
Just as it would be bizarre to say that Iron Maiden played thrash metal or death metal, it was confusing and inaccurate to refer to acts like Kreator and Carcass as heavy metal.
Yet people persisted.
Again, the swift rate of the music's evolution was largely to blame for this, though it quickly reached a point of extreme incongruity.
By the time heavy metal suffered its abrupt death in the early '90s and was replaced by newer and drastically different forms of music, it became particularly odd for fans, journalists, and TV personalities to continue to slap the heavy metal name on non-melodic recordings with industrial, hip-hop, and electronic influences that bore no relationship to the heavy metal sound.
Coal Chamber - "Loco" (1997)
No one had insisted on classifying death metal acts like Morbid Angel and Obituary as "hard rock," yet mystifyingly, the "heavy metal" label was carried forward to a new era of unrelated artists including Slipknot and Coal Chamber.
The pattern has only expanded from there, and the name “heavy metal” is now commonly and confusingly applied to hundreds of different music styles.
What’s in a Name?
Heavy metal is the original form of metal music, and it's the foundation on which all other metal subgenres are built. With over 40 years of metal history behind us, there's little reason for ambiguity about heavy metal's characteristics, its name, or its valuable role in music history.
Thousands of clear-cut traditional heavy metal albums have been produced over the past several decades, including groundbreaking entries that remain among the most influential recordings in music history.
In order to respect the pioneering creations from the early '80s, as well as the diverse range of music they inspired, it's worth reserving the name "heavy metal" exclusively for music made in heavy metal's signature style.