McDaniels grew up in Hollis, Queens, New York.[1] He attended Catholic schools including St. John's University in New York City.

McDaniels first became interested in hip hop music after listening to recordings of Grandmaster Flash & the Furious Five. In 1978, McDaniels taught himself to DJ in the basement of his parents' home, using turntables and a mixer given to him by his older brother, Alford. During this period he adopted the stage name "Grandmaster Get High".

Later that year, McDaniels sold his DJ equipment, after his friend Joseph "Run" Simmons acquired his own turntables and mixer.[citation needed] After Jam-Master Jay, who was the best DJ in their hometown of Hollis joined the group, Run encouraged McDaniels to rap rather than DJ. Gradually, McDaniels came to prefer rapping to mixing records, and adopted the nickname of "Easy D". In 1981, he dropped the "Easy D" moniker in favor of "DMcD", the way he signed his work in school, and then to the shorter "D.M.C.". D.M.C. alternately stood for "Devastating Mic Controller" or his nickname since childhood, "Darryl Mac".