Classified by most as a rock, or nu metal band, Disturbed is also regarded by some critics as alternative rock alternative metal, heavy metal and rap metal. However, when asked about die-hard heavy metal fans not finding Disturbed heavy enough, frontman David Draiman stated:
"We probably have too much melody going on or we're not quite as turbulent or caustic. While I really love that type of music, it's not what we try to do. If we have to place things in context, we're more hard rock than heavy metal these days."
"The secret is that we were never really part of any particular trend, although we definitely benefited from the popularity of what was called nu-metal at the time," Draiman says. "We never had the stereotypical attributes that those bands had. We don’t rap; there’s no turntable involved; no fusion in that respect. We play, in my opinion, classic metal. Black Sabbath, Iron Maiden, Judas Priest, Metallica, Pantera: These are the bands that made us want to play.
Allmusic reviewer Bradley Torreano described the album Believe as "taking the sort of jump that their heroes in Soundgarden and Pantera made after their respective breakthrough records". He also described the title track as moving "from a brutal chug to a sweeping chorus that suddenly stops in its tracks and turns into a winding riff that recalls the work of vintage James Hetfield".
According to frontman David Draiman on the band's home documentary M.O.L., the lyrics that he writes are inspired by life experience, perception, and actual experiences of his own, and he stated that he likes to present his ideas with cryptic lyrics.