1. Djent
Djent is used to describe a certain kind of guitar tone characterized by medium-high gain, a quick-release noise gate to emphasize staccato playing, a cut of most bass below 200Hz for a tight low end, a slight boost around 800hz for clarity, and a noticeable boost around 1.6Khz to emphasize pick attack. When a two-octave power chord is palm-muted with this tone, a "djent" sound is created rather than the typical chunkier sound.
Djent also refers to repeated staccato playing of the lowest-pitch string on a detuned 6 string or 7 string guitar with a powerful attack such that the string goes very slightly sharp upon the pick's release from the string. Lower-gauge strings are used to facilitate this.
Djent tone is many times created using a Line 6 amp modeling product such as the Pod series or the Axe-Fx. When possible, an amp model such as the Big Bottom or Modern High Gain on these devices is used in conjunction with a modeled Tube Screamer in front. Engl and Mesa amplifiers are typically used when tube amplification is preferred.
Djent is widely acknowledged to have come first from Meshuggah, but Misha 'Bulb' Mansoor has arguably popularized the sound. Djent's typical uses give rise to a "genre" of djent that is characterized by hi-fi compressed production, polyrhythmic/staccato distorted riffs and ambient clean passages which make liberal use of 9 and other "jazzy" chords. Electronica influences such as glitchy percussion and synthesizers are also incorporated.