We see everything from the narrator's point of view, so exposition about the world is limited to what impinges directly on him and the story he's telling. Considering how old the world is, we learn very little about its history, which I think is a good thing.
Neal StephensonWait a minute, Juanita. Make up your mind. This Snow Crash thingโis it a virus, a drug, or a religion?" Juanita shrugs. "What's the difference?
Neal StephensonI really am just trying to tell stories. But stories are often grounded in larger events and themes. They don't have to be - there's a big literature of trailer-park, kitchen-table fiction that's just about goings-on in the lives of ordinary people - but my own tastes run toward stories that in addition to being good stories are set against a backdrop that is interesting to read and learn about.
Neal Stephenson