Via 1UP:

It doesn't require too much of a leap in logic to assume that, without Sonic the Hedgehog, many of us today wouldn't even know what a hedgehog is. More importantly, Sonic's influence on the world of videogaming can't be overstated. In a time when the industry had begun to deteriorate around the weakening shoulders of the Atari and its clones, the rivalry-driven duo of Sonic and Mario single-handedly made videogames cool again. While Mario's claim to fame was level design that heavily favored the accurate jumper, Sonic was all about speed and cat-like reflexes. Through the years of the 2D sprite, Sonic and Mario battled back and forth as equally matched opponents. With the arrival of 3D graphics hitting the console scene, Mario swiftly took the upper hand, effortlessly bringing innovative platforming elements into what was then next-gen. Sonic didn't fare so well through the transition, quickly becoming mired in an inability to seamlessly incorporate its trademark devotion to speed into a three-dimensional environment.

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