1. Melle Mel (popularized rap conventions we're familiar w/ now: "yes, yes y'all", "hip to the hop", one of the first to take emceeing from the dj booth to the stage)
2. Grandmaster Caz (most prolific old school emcee, basically first ghost-writer with Rapper's Delight)
3. Run/DMC (first rappers to bring street image to public eye)
4. Rakim (first real lyrical emcee)
5. Kool G. Rap (not the first, but first greatest gangsta rapper. his flow influenced Pun, Biggie, etc.)
honorable mentions go to: KRS One (inventor of many styles, popularized dancehall influence on hip hop),Cold Crush Brothers (one of the first groups to make emceeing entertaining). Busy Bee (famous battle emcee),Kool Moe Dee (early educated rapper and battle emcee), LL Cool J (very image conscious, one of first pop cross-overs), Public Enemy (militant rap) and Jungle Brothers (first positive rappers)...
what do you think?