^^ Released in January 1981, I do believe this is the first Rap song to ever get mainstream play even though it's almost halfway through the song before anything even remotely resembling a Rap cadence begins....

http://youtube.com/watch?v=xHPikUPlRD8
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I'd rather be ignorant than stupid. Ignorance implies a lack of knowledge which is easily correctable through education. Stupidity implies an inability to learn. Therefore; ignorance is temporary, stupidity is forever!