We process much more information. That’s the major difference. In general you want a big round head, a lot of neural density, and the lowest possible friction of transmission (white matter).
In addition to processing more information we often identify increasingly subtle (more remote) patterns.
And because of this we can work longer at learning – and some of us (I am certainly one of them) feel anxiety, depression, or pain if we are not learning. So not only can we learn more faster, but we can learn more because we can learn more hours per day.
The more information we have, the more remote the patterns we see, the more we rely on that information and the less on intuition, norm, tradition, and the opinions and ideas of others.
Additionally, some people have better short term memories and can hold larger static models. ( Hawking is a great example, but so are many others). I do not have this particular ability and I find that it is what differentiates me from the people who are above me.
Additionally some people have superior verbal abilities and can describe what they think of more accessibly. (Noam Chomsky is smarter than I am, in both short term memory and verbal ability, and rarely loses his place no matter how convoluted the conversational route. )
Some of us have more discipline, more conscientiousness, and skepticism and we’re possibly more autistic (which is the result of high neuronal density anyway), and we simply make fewer errors than others. This is very rare.
We mature at different rates. Some of us have exceptional abilities in childhood and have nervous breakdowns when we reach young adulthood. (This is a subject I study now and then.) Others mature normally. Others of us mature more slowly.
Normies are quite frustrating really. I had the great fortune to have a very old professor of contract law, who told me my sophomore year that “The world is not meant for us. It is meant for them. We are prisoners of their world. And the best we can do is help them through it.” And I found that advice to be profoundly useful in ending the the feeling that normies run the world, like children at a birthday party running with scissors. 😉