South Myrtle is where the old pavillion - amusement park -was. It has all the arcades, Ripley's and most of the minature golf. It's the older traditional Myrtle Beach.
North Myrtle is an outlet shopping mecca. There's a lot to do there too, but not as many people. Personally, I think North Myrtle is way cleaner! South Myrtle is where all the kids go for graduation. Depends on what you're going for.