This is a unique work, different than previous books. A departure from the kind of scifi one might expect from a Stephenson novel. Its an origin story of a make-believe world that exists in a computer. Nearly all of the 890 page book is that story, using mostly characters from the first 15% of the book that happen outside the computer. I enjoyed it to the end, though perhaps because I was unwittingly exposed to genres I wouldn't have picked outright.