Are there different kinds of imagination?

Here is what I'm thinking (your answer doesn't have to be specifically about what I just wrote; I just wanted to put down my train of thought):

A commonly listed sign of autism is lacking imaginative play skills. I've always thought these kids lack imaginative *social* play skills, which makes sense because they lack social understanding in general. The reason I've always had a hard time saying they don't have imagination at all, is that I think my kids do…
I don't know, maybe it's just that I want them to. But, for example, one of my kids will spend hours moving around objects (he'll put them in a row, then in a circle, then in a pile, then bulldoze the pile, etc.). So what is he doing? Why is this entertaining? I don't think he's just thinking "Line. Circle. Pile"… I mean maybe he is… But I think it's more likely that something else is going on- something IMAGINATIVE! Not socially imaginative, but imaginative in some way. He also now plays minecraft (computer game) in which he makes these super cool structures that I feel like it takes some sort of imagination (creativity?) to come up with.

I remember doing a lot of imaginative play as a child, but all of it involved social interaction. Sometimes we'd pretend to be animals. I remember one game I played a lot for a while was we were a family of squirrels but the whole point of the game was about our family interaction- it wasn't about being a squirrel at all. So I can't even describe what this "other kind of imagination" I'm talking about is. Maybe that is because it doesn't exist…

The child I was talking about above doesn't speak and I don't think he thinks in words either. I don't know how he thinks or what he thinks. Maybe that fact changes it. Maybe I'm just way off. I have no idea. It's just something I was thinking about. So what do you think?

Lining stuff up doesn't have to involve "imaginary play" at all. I find things that are sorted (lined up, sorted by color, by shape or whatever) to have a soothing effect and they make me happy to look at.

I think that while imagination and creativity are related, they are not the same.