Doom metal is a form of heavy metal that emerged as a recognized metal sub-genre in the early/mid-1980s. Doom metal is heavier and slower than other metal genres. Lyrics play a very important role in this genre, and are traditionally rife with pessimism, evoking an atmosphere of darkness, despair and misery. Musically, doom metal is strongly influenced by the early work of Black Sabbath. A number of early Black Sabbath tracks, such as "Black Sabbath" are often considered embryonic or prototypical doom metal songs.