This paper is an "intro" to String Theory. Well, at least that's what the paper claims.
Now, don't think you actually will learn much from it, because String Theory is highly mathematical, and this paper doesn't even present much, if any, of the theory. All it does is present a superficial argument for String Theory. So in that sense, this is as good of an intro to laymen as any. You'll get some general idea on what String theory is, but nothing substantial beyond that. I won't be surprised if, after reading this, you end up with more questions than you started with.