Rock 'n' roll seems to nestle an almost infinite number of distinct musical genres under its very broad umbrella, but when one of those genres hangs around long enough – as heavy metal has for close to 50 years now – it’s bound to spawn a range of sub-genres all its own.

How many? Honestly, we stopped counting after we crossed the half-century mark, because even some of metal’s more popular sub-genres contain a vast range of sub-subgenres, themselves. In other words, we could split subgenre "hairs" until the cows come home and never stop.

Fact is, whether you dig your metal doomy or thrashing, traditional or progressive, groovy or gothy, deathly or, uh, black-ly, and a vast assortment of "-cores," we can all agree what matters is that they're HEAVY.

So, as you'll see, our present gallery covers what we believe to be the 40 most popular and well-established heavy metal subgenres, and we'll give ourselves the option to expand the list before too long. Check out the best releases from each metal subgenre in the gallery below.

The Best Metal Album From 40 Subgenres

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