At first, he was a blue hedgehog sprite with feet that blurred because he ran so fast. But that was 18 years ago (yeah, where's the time gone?) and he's been redrawn over and over again to fit new technology. In fact, unbelievably, Sonic the Hedgehog has appeared on screens in some 50 guises.
But it's not enough to just show you them all. The internet needs to know which is best.