I know very little about heavy metal music. Are you familiar with the genre?
Yes, heave metal  is a genre of rock music that developed in the late 1960s in the united kigndom
What characteristics define heavy metal music?
With roots in blues rock and psychedelic/acid rock they have massive sound, extended guitar solos, and over all loud
Who are some of the most famous heavy metal bands?
In 1968, three of the genre's most famous acts, Led Zeppelin, Black Sabbath and Deep Purple but at the moment i am not familiar
Is the genre still popular today?
Yes it is really popular till this day Though they came to attract wide audiences, they were often derided by critics