Like every other genre that people seek out in great numbers, science fiction now has sub-genres. Nothing spectacular about them, you’ll find the same ones in other genres. Except steampunk. I’m not sure that’s anywhere else. Let me know if it is, I don’t read a lot of it so I might have missed it elsewhere.
The thing I find fascinating about science fiction sub-genres is that they always existed, they just weren’t labeled. The Wild, Wild, Wild, Wild West was an early version of steampunk. I’m not sure I have the right number of ‘wild’s in the title, but you get the idea. It was a fun TV show that paved the way for the steampunk that’s out there now in many types of media, including several movies.
I loved Asaac Asimov’s Caves of Steel. It never occurred to me that it was science fiction mystery. That’s because it was written before sub-genres came into existence.
Science fiction romance is a little different. Romances were often included in every kind of science fiction story out there but they weren’t the main focus of the story. The thing is, even now when there are web sites that cater to science fiction romance, the romance isn’t always as prominent as it is in most romances.
And there’s science eco-fiction. Think Dune, which was one of the first. Or many of Jules Verne’s books.
There are as many sub-genres as you’d expect in a wildly popular genre.
But always, always, in science fiction, the backbone of the story is the science… or what passes for science in the writer’s mind … and everything else is layered onto that. Make no mistake, characters and their journey through whatever situation they face is so essential that a story that contains wonderfully compelling science and lousy characters won’t sell. But, without that basic science component, it won’t even make it through the editing process. Not so with romance, in which the characters can be the whole story. Not so either with mysteries in which the detective can be as important as the mystery.
In science fiction, the science is truly important and there’s a way science fiction writers use it to help them create a story. It’s called world-building, it’s important, and more about it later.