So here's the reality: Only about 10% of autistics have a savant skill, and it's a lot less flashy than Rain Man. It's just a skill that you're so naturally good at that you pick it up way more quickly than anybody else, and get way better at it than anybody else--it's like your brain is specialized for it. Neurotypicals, by that definition, can be considered to be social savants. Any NT toddler learning language has a savant-like language acquisition ability that they won't have when they're grown.
Point being: Savant skills don't define autism, and they aren't actually that weird in the first place. If you're neurotypical, you have probably had the experience of looking at somebody and just knowing how they're feeling, or following along with others' actions without having to think much about it. That's pretty much the way somebody with a savant skill learns things like that--it just feels natural to them to do it, comes easily.
Another term for a savant skill is "splinter skill", and I prefer that term because people don't associate it nearly as much with calendar-calculating, card-counting stereotypes. If I could popularize any term for it, I'd use the term "cognitive specialty", because that's basically what a savant skill or splinter skill is.
So let's talk about what a splinter skill really looks like, in everyday life. It's a very specific skill--not like a broad talent, but quite a small specialty. For example, a talent would be, "I'm good at doing math problems." A splinter skill would be, "I can prime-factor numbers very quickly and accurately." Most people with splinter skills aren't prodigious savants (a "prodigious savant" is a term for someone with the really flashy savant syndrome, like Kim Peek or Daniel Tammet). They just have this one thing that they're really good at. For example, I know of one young woman with an intellectual disability who is so hyperlexic that she learned to read at three, and in adulthood she has such natural grammar and spelling ability that she literally never makes mistakes. She's a grammar specialist. She's not a novelist; she probably doesn't study English literature; she doesn't even have any particular ability to write a good research paper. But her grammar and spelling are perfect, and have been since she was very young. Another young man had a very good spatial memory, and he worked at a warehouse. He could tell you where any product in that warehouse was located, without a map or a manifest or anything else. Those are typical examples of splinter skills.
I have a minor splinter skill. I can improvise a harmony line to any melody after hearing it once. Sometimes I can improvise the harmony during the first hearing because I am so familiar with the patterns that music takes.
I am relatively good at learning music. I play the piano passably, can sing on-key, and enjoy listening to complex classical pieces as well as the simpler, more catchy songs from musicals. My musical ability isn't a splinter skill; it's a talent. I started out with a knack for music, but I had to work to learn to play the piano, and while I've always been very good at differentiating pitches, I still had to learn how to control my voice so that the pitch I was thinking of was the one that I actually produced. (By the way, no, I don't have perfect pitch. I can guess a note within a couple of steps, and I can recognize an interval intuitively, but to me, there's nothing about a C that's distinct from a D, even though I can tell you it's the exact same difference as between an F and a G.)
I'm not actually a gifted musician in general. I'm good at music, sure, but not amazing. That's what a splinter skill is--it's very precise. It doesn't give me global ability in music; just in that one specific part of music.
Music in general, I had to learn. But the harmony thing... That came early, easily, and so naturally that I didn't realize that other people couldn't do it. I remember sitting in church as a kid, listening to a woman nearby singing harmony out of the hymnbook. I didn't realize she was following the notes. At that point in my life, I didn't know how to read music at all. I just heard that she was singing different notes that sounded good with the melody. I thought, "I can do that," and so I tried it, and I found that I learned it quickly and easily. Nowadays, I often sing an improvised harmony line to those Broadway musicals, at least when I'm alone and only my cats are there to hear me. It's just fun.
And it's not something that other people can't learn, either. It's not some hugely mysterious art. Any college music student probably knows enough about music to improvise a harmony line. It's just that I did it much younger, and it took much less learning. That's a typical splinter skill. See? It's not so intimidatingly weird after all, is it?
By the way, the idea that savant skills can't be creative--that's just bunk! Yeah, I started out with the bare mechanics of it; I liked the way sounds fit together like puzzle pieces. But as the years passed and I studied music and listened to more of it, I learned how to use that little brain quirk of mine to understand music more deeply and fully. When I listen to music, I hear all the little pieces of it, and I think about how they come together. It's like seeing all the brush strokes in a painting. If I were one of those artistic savants, I might've started out just copying from my environment, but I would've gone on to enjoy art for its own sake. For somebody with a splinter skill, the simple joy of fitting together harmonies, or playing with numbers, or drawing what they see, is entertainment enough that they generally want to learn more about it.
I am starting to wonder whether splinter skills are truly so rare. Marginal ones, like mine, are probably quite common on the autism spectrum and off it, especially among people who are neurodiverse in some way. If you think about it, savant syndrome isn't so far removed from the average person's experience at all--it's just an extreme version of what you normally see. Some people learn a subject more easily than most. Some people learn that subject more easily than they learn other things. Exaggerate that, specialize further, and you have a minor splinter skill like mine, which comes easily enough to someone who's a professional in the area and is unique mostly because they learn it so early and so quickly. Further on, you have extreme savants and then prodigious savants with multiple savant skills, whose abilities are so specialized that they would take years of training for a typical person. (The feat of memorizing a pageful of numbers in a few minutes can be performed by trained memory champions.)
When I sing a harmony line nowadays, I don't want people to look at me and think, "Wow, that's amazing!", as though I were a performing animal jumping through a hoop. I want them to think, "Wow, isn't the human brain interesting?" Because it is. And because I'm as human as they are. (Thankfully, now that I'm thirty, it's no longer odd for me to sing a harmony line in church. Plenty of people learn them from each other and read them from the hymnbooks. But when I was a kid... I used to get people turning around in their seats and complimenting me after the hymn ended.)
It's the strangest thing--the more extreme a person's savant skills, the less human they seem to be to others. I don't like that. I think Daniel Tammet is very lucky to still be thought of as human, because he's also so very articulate and is interested in brain science, and so scientists have to see him as a person instead of a test subject. Not all savants are that lucky. Savant syndrome is associated with brain damage, with developmental delay. In the worst case, a person could be seen as nothing but a mobile unit for transporting his savant skills. The person gets swallowed up by those flashy abilities, and nobody cares about what he likes and thinks and feels, what his ambitions are, who he loves. He's just "the savant". And that's scary.
Just like a disabled person might be seen as merely the sum of their disabilities, a person can also be seen as only the sum of their talents. That gifted kid is "that gifted kid"--everybody talks about his being able to take calculus at age twelve, but nobody really thinks about who he is as a person. Say he wants to become a paramedic, and loves baking cookies with Grandma, and sneaks his dog onto his bed every night even though he knows Mom hates the way the dog hair gets on the sheets... Nobody thinks about that stuff. It's all about the calculus. But what's with that? The dog-loving, cookie-baking kid with ambitions of riding in an ambulance for a living is just as real as the kid who juggles integrals.
And if you're both talented and disabled... oh, then you're really in for it! Either you're disabled, and it's "just a splinter skill" and you're not truly talented or truly creative; or you're gifted, and you should just "overcome your disability" and go be Stephen Hawking or something. (Nothing against Hawking, by the way. He does have a real talent for making physics accessible to high-schoolers, and for that I'll be forever grateful. But do they really have to constantly point out that he has ALS? We knew that after the first time they covered it; can we get to the physics now?)
People are just too complex to distill down like that. When a person has a highly visible or unusual trait like a savant skill, there's always the risk that other people will see that trait as fully defining them, as though there's nothing else to them. In reality, though, every person is so extremely complicated that even a hundred traits couldn't define them, let alone one. Perhaps that's why I like studying psychology so much--it constantly reminds me that even when you think you know what "human being" means, there's always more to learn.