"Microphone Fiend" was the second single released from the hip hop duo Eric B. & Rakim's second album Follow the Leader. The song became something of a signature song for rapper Rakim, and AllMusic's Steve Huey says the song "weaves references to substance addiction throughout in explaining why Rakim can't keep away from the mic." Featuring a prominent sample of Average White Band's 1975 hit "School Boy Crush", the song was further evidence of Eric B.'s fondness for soul samples and became one of the most quoted songs in hip hop.

Microphone Fiend contains many of the elements that are often sited as having been prominent in the golden age of hip hop, such as samples, record scratching, and vocal syncopation. The song has been covered numerous times and has become a 'standard' of hip-hop music. The most notable cover was performed by Rage Against the Machine for their album Renegades.

...
Wikipedia