Technical death metal (sometimes called tech death) is a subgenreof death metal that focuses on complex rhythms, riffs and song structures. As death metal bands evolved, some experimented with elements from a variety of genres. As a result of such experimentation, exemplified by Suffocation, Cryptopsy and Gorguts, the subgenre of technical death metal established itself as a complex and varied musical style. Phil Freeman, ex-editor of Metal Edge, has described it as "the hidden side of its genre, having more in common with prog-rock and jazz fusion than with the mechanistic, Satan-obsessed grinding that’s the music’s dominant public image.
Technical experimentations in death metal began in the late 1980s and early 1990s by bands such as Death, Atheist and Cynic. In 1989 Atheist's debut album Piece of Time was released, followed by Nocturnus's The Key, in 1990. In 1991, Death released Human. This and later Death albums have proven influential on 1990s technical death metal bands. Other early technical death metal albums include Considered Dead(1991) by and (1993) by Cynic.