Ever wondered just how many book genres there are out there? No, me neither, nevertheless I found this map from Book Country fascinating:
There’s a general description and some landmark books for each one.
djpaterson
NetGalley Professional Reader
NetGalley Challenge 2015
djpaterson 
Medical thriller? Now that’s a sub-genre I could have lived without classifying! 🙂
It was the thought of Hard SF and Soft SF that made me smile. I’ve enjoyed a bit of both in my time!
I like romantic suspense, does it mean they’re worrying about whether they’re going to get any or not?
🙂
Medical thriller? Yeah, I’ve never seen that in a book genre. It seems popular on TV, though! Is there any reason why these genres were placed in the order they were—horizontally/vertically, etc?
No idea about the ordering of the genres, but I have read a medical thriller (some time ago, now) – A Case of Need by Michael Crichton.