A brutal sub-genre of heavy metal. Misplaced anger is often put towards this genre by ignorant people who think jazz is really avant-garde.
Death metal usually includes but is not limited to fast riffage, growling vocals, and blast beats. Modern death metal has some grindcore influence. Yes, it does take talent to vocalize like that. Record yourself "growling" and let's see how professinal you sound.
Death metal bands: Morbid Angel, Severed Savior, Dying Fetus, Misery Index, Massacre, Immolation, Suffocation, Malevolent Creation, Impaled, and many more.
The following band is not death metal: Slipknot. Slipknot is mallcore. Deal with it.