The Best Science-Fiction Subgenres

Sophie Playle

Science fiction is just about space travel and aliens, right? Nope, nope and nope again. The genre covers a lot more ground than you might expect.

In my humble opinion, these are the best science fiction subgenres – that’s to say, these are my favourites, with some recommended reading thrown in for good measure.

What is Science Fiction?

Science fiction is one of my favourite genres because there’s something about the plausibility of the science mixed with the imagination of the fictional that blows my mind. The boundaries can sometimes seem blurry between fantasy and science fiction, but the main difference between the genres is this tension between imagination and reality.

Generally, I think all science fiction can be divided into two main categories: hard science fiction and soft science fiction.

Hard science fiction is driven more by ideas than characterisation.

In hard science fiction stories, plausible science and technology are central to the plot. If your story is set on a lunar colony, for example, issues of technology may be of greater concern than a character’s personal life. To write effectively hard science fiction, an author must generally have a good grasp of the scientific principles involved. Much classic science fiction, including the earlier works of Asimov and Heinlein, fall into this category.

Soft science fiction is character-driven, with emphasis on society and psychology.

In soft science fiction, the emphasis is not so much on how technology works but how it affects individuals or social groups. Robert Silverberg’s short story ‘To See the Invisible Man’, for example, focuses on how a futuristic form of punishment affects the individual and the surrounding society. Ursula K. LeGuin is a noted author of soft science fiction.

First contact/alien invasion

I know I said sci-fi isn’t just about aliens, but … a lot of it is. The first contact subgenre explores the initial meeting between humans and aliens – whether this meeting is on earth, in space or on another planet. The alien invasion story could be a first contact story (like The War of the World by HG Wells) but it’s not always (for instance, in Ender’s Game by Orson Scott Card, the war with the aliens is ongoing).

Time travel

Time travel is the place where fantasy and historical fiction come together with sci-fi. But before you start to work out your time travel plot, you have to decide which way in time to send your main character: forward or backward. And then you need to decide how to get them there.

Most time travel sci-fi has its characters going backwards into the past (like in Kindred by Octavia E. Butler), perhaps because it’s so interesting to think about how our actions in the past can have ramifications on the present.

There aren’t as many novels that catapult characters into the future. The Time Machine by HG Wells is perhaps the most famous (and arguably the novel that gave birth to this subgenre in the first place).

Space opera

Best described as ripping yarns in space, the hallmark of space opera is bigness. You have colonial ambition on a grand scale, gigantic tools and weapons, massive chauvinism, and of course the epic sweep of space as a backdrop.

Although exhilarating, classic space opera is often full of big men being big heroes in big settings where women – if they’re lucky – just make the tea. Generally, I’m not a fan of this subgenre. But there are some notable exceptions.

Isaac Asimov is known as the godfather of space opera, with the Foundation series being some of his most famous novels. Frank Herburt’s Dune is to science fiction what The Lord of the Rings is to fantasy. It’s the world’s best-selling science fiction novel of all time, and is space opera at it’s finest.

Robot fiction/

This is exactly what it says on the tin: fiction in which the science of robotics is a central theme. Often, robot fiction includes exploration of artificial intelligence and sometimes the fusion of humans and technology (cyborgs). Isaac Asimov is a grandmaster of this subgenre, too – espcially his Robot series. The Windup Girl by Paolo Bacigalupi is one of my favourite novels in this subgenre published in recent years.

Military sci-fi

Although military sci-fi covers any work that touches on the subject of war and the armed forces, the more interesting examples have nuances.

The 1985 novel Ender’s Game by Orson Scott Card is a good example. The first in a five novel series, Ender’s Game introduces child soldier Ender Wiggin, trained from a very young age by battle games in zero gravity. It’s a tribute to Card’s handling of the subject that this book is on the recommended reading list for the US Marine Corps.

Interestingly, I think most hard science fiction stories can be found in the classics. Contemporary sci-fi is much more likely to blend the boundaries between genres and have a focus on character. Perhaps this is because as we move into the future, what once seemed like mind-blowing concepts now feel so very plausible, just around the corner. Because of this, we’re less impressed by concepts alone and are more interested in characters and themes.

Sophie Playleis a professional fiction editor. She specialises in developmental editing, critiquing and copy-editing, and loves working with authors and publishers who are passionate about high-quality storytelling. Speculative fiction, fantasy, science fiction and literary fiction are her genres of choice. She's an Advanced Professional Member of the Chartered Institute of Editing and Proofreading and has a Creative Writing MA from Royal Holloway, University of London. Find out more:

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