Originally Posted by Wikipedia

Instrumental hip hop is hip hop music without vocals. Hip hop as a general rule consists of two elements: an instrumental track (the "beat") and a vocal track (the "rap"). The artist who crafts the beat is the producer, and the one who crafts the rap is the MC. In this format, the rap is almost always the primary focus of the song, providing most of the complexity and variation over a more or less repetitive beat.


Instrumental hip hop is therefore hip hop music without emcee accompaniment. This format affords the producer the flexibility to create more complex, richly detailed and varied instrumentals, with less emphasis on vocals. Songs of this genre may wander off in different musical directions without the vocal constraints of the MC.


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The release of DJ Shadow's debut album Endtroducing..... in 1996 saw the beginnings of a movement in instrumental hip hop. Relying mainly on a combination of sampled funk, hip hop and film score, DJ Shadow's innovative sample arrangements influenced countless producers and musicians. In recent years, artists such as RJD2, J Dilla, Pete Rock, MF Doom, Danny!, Nujabes, Madlib, Wax Tailor, DJ Babu and Blockhead have garnered critical acclaim with a number of instrumental hip hop albums.

Originally Posted by RYM

Essentially Hip Hop without an MC, instrumental hip hop can take many complex or basic forms and span a wide variety of different styles from artist to artist. Hip Hop producers release these sorts of albums in a variety of ways: some can be a collection of used and unused beats such as Special Herbs, Volumes 1-2 or conceptual releases like Endtroducing..... and Shades of Blue. Other producers will release instrumentals from a specific album, such as 2001: Instrumentals Only.