I think I may have a different perspective from most people on this board in that I have been an absolute lover of Hip Hop since I was very young (probably about 5 years old). So here's a little story that must be told:

If you had to name somebody to be the "creator" of Hip Hop, it would be a Jamaican immigrant to the Bronx who went by DJ Kool Herc. Kool Herc was an amateur DJ during the 70's playing small birthday parties and stuff when he noticed something that would change music forever. He saw that people would have big reactions to segments in a song maybe 10-30 seconds long called the break. This was just the stripped down funk and rythym that would get crowds moving and people dancing. He figured he could isolate the break and play it over and over again so that he could keep the crowd moving and the people dancing. So he used two turntables playing the same record and a mixer to cut between them. Well this caught on real quick and soon enough, everybody in the ghetto was buying turntables. There would be block parties and club parties with break dancing and all sorts of shit. NOW, here's where rapping starts. During a show, the DJ would never get on the mic and address the crowd. So you needed somebody to engage people. Thus, the MC was born. He could get on the mic and get the crowd pumped. Sometimes he'd just say things like "All the ho's say ho!" Or, "Throw your hands in the air!" Well from this, came MC's saying things rythmically or with the DJ's beat and call and response type stuff. So maybe the MC would say, "Yes, yes, yall! And you don't stop! To the beat yall! And you don't stop!" Since rhymes have always sounded good to human ears, the chantings of the MC started to rhyme. The rest is history.