Bascially, a commercial model is used to sell clothing. They need to have the look of you and me, but a little prettier and thinner. High fashion models are edgy, bold, tall, unconvential, not as "pretty" as commercial models

I actually watch a little bit of America's Next Top Model. I watched cycle 15 where a woman by the name of Ann Ward had won. If you have never seen this show and more specifically this cycle, here's her picture: