A great deal of content about whatever Neal Stephenson is nerding out about at the time he's writing the book that forms the world-building (The metaverse in Snow Crash, MMORPGs in REAMDE).
There will be random digressions about other things he's nerding out about that don't amount to enough to be a major feature of the world (volcanic glass knives in Snow Crash, tuck-pointing masonry in REAMDE) that he nonetheless works into the story.
Some plot happens in this world, followed by an ending of highly variable quality. He ties Snow Crash together fairly well, as I recall. REAMDE, I was less impressed by.
For context, I've read everything of his except the Baroque Cycle up to Seveneves. He's pretty consistent in sticking to this format.
In my opinion his best writing is In The Beginning Was The Command Line[0]. I particularly like the quote "I use eMacs, which might be thought of as a thermonuclear word processor." It makes me smile despite the fact that I'm a vi person. It's also uncharacteristicly short for his work.
[0] https://smorgasborg.artlung.com/C_R_Y_P_T_O_N_O_M_I_C_O_N.sh...