I'm very fond of fiction, specificly, non-reality-based, futuristic fiction which takes a look at our world many years hence or other worlds and postulates what events might transpire, or what philosophies might be explored. Often, any futuristic story is referred to as "science fiction", but over time, the genre has split into various "segments". It is my belief that these "segments" have evolved to describe in greater detail some shared beliefs that we might have about the future of mankind. Alternatively, these genres also can become a stage for specific moral plays or philosophies that the author might wish to experiment with.
In the following descriptions, I have attempted to split up the various segments of the science fiction genre according to how I have seen them presented in books, movies, comics, and role-playing games. These are not rigid guidelines; indeed, many futuristic stories will have elements of more than one genre, or might experiment with adding something new. The "Aeon Flux" cartoons are an example of a setting that defies rigid classification into any of the genres I describe, but contains elements of nearly all of them.
In this writing, I have used numerous names which are likely copyrighted, trademarked, or otherwise protected or reserved. Trust me when I tell you that they all belong to their respective owners.
Daniel Pryor made some good additions to this list to help make it more complete. Specifically, he added the 'Pure Science Fiction' genre.
So named because of the movie by the same name which popularized this genre exceedingly. This is not so much "science fiction", but it is futuristic.
Deserts, cars and guns. Gasoline and water are priceless, cacti and dust are plentiful. People tend to live in small "clans" or bands on the edge of nowhere. Life is lived on the road. Populations are small and sparse. Often this is explained by some devestating nuclear war or disease that took place in the recent past.
Mostly humans. Occasionally some mutant humans or mutant animals (i.e. Tank Girl's Kangaroo boyfriend) will show up. These mutants are typically explained by nuclear radiation following the aforementioned war. Often, Native / Aboriginal Peoples (colloquially known as "Indians") will have a presence, typically a dominant presence.
All too often, people use this genre to show what might happen in a post-nuclear-hollocaust or post-plague world, where populations are decimated and people revert to more primitive societies/technologies. As such, you see a lot of talk about the sociality of the "tribe".
Movies: Mad Max / Road Warrior / Beyond Thunderdome, Steel Dawn (horrible B movie)
Role-Playing Games: Road Hogs, Car Wars, Twilight 2000
Comics: Tank Girl, Newstralia
Near-futuristic, bleak, very high-tech. Big megacorps in enormous glittery buildings, and huge slums. Very heavily populated cities (a la Tokyo).
Megacorps, Runners, Street Samauri, Cyber-dudes, Razor-girls, and the great unwashed. Many of the "major" character types are "wetwired" with some cyberware or bioware. The Mafia typically exists in some form. Governments are typically miniscule and irrelevant, supplanted by the Feudal-style rule of the Megacorps. Southeast-Asian peoples are typically portrayed as the upper / ruling-class.
Cyberpunk genres make a good platform for discussing social principles (responsibilities of businesses, disparities between rich and poor). It also is often a demonstration of how we interact with technology, including how it can alienate us, how it can "blend" with us (i.e. 'wetware') and what it means to our privacy.
Movies / TV Shows: Blade Runner, Max Headroom, The Running Man, Strange Days, Johnny Mneumonic, TekWar
Role-Playing Games: Shadowrun, Cyberpunk
Books: Neuromancer, Snow Crash, Mondo 2000 (rag)
Or "Action / Thriller gone Futuristic".
Distant future. Bleak, fearful, violent. This is not a "utopian" future, but just the opposite. Kind of what the 'Cyberpunk' genre would grow into if you were to stir and wait a thousand years. Typical settings include space-stations, distant-world outposts, and way overpopulated "home" planets. This is a bit of a "wild west" coupled with the typical "monster movie", only instead of six-shooters, the characters pack plasma rifles.
At it's most basic level, this genre is simply a shoot-em-up slug-fest: Lots of big, bad buggy aliens to kill; Lots of warrior aliens to wrestle with; Lots of maniacal robots to blow up.
At another level, this genre serves to illustrate our fears about what might be "out there", alien and unknown--The "Bugs" characters are a good illustration of this. It also shows us how human nature does not change much over time: we will always be fearful, we will always be struggling/fighting, we will never achieve utopia, etc.
Movies / TV Shows: Aliens, Starship Troopers (originally a book), Predator, Total Recall, Babylon 5 (to some extent)
Comics: Aliens vs. Predator
Computer Games: Doom, StarCraft
This is where it all got started.
Space ships, ray guns, warp-drives, hover-cars, and space stations. Typically, this genre features very advanced technology, i.e. non-invasive surgery, faster-than-light space travel, data storage in crystals, anti-gravity, time-travel, and the like. This genre uses real science but also invents "new" science or creatures (i.e. Star Trek)
Humans, aliens, and robots in all forms and flavors. By this time, it is assumed that cloning is commonplace, so you will often see clones here and there.
Very often, the villains in Classic Sci-Fi stories will not be human, or even human-like; the villain can often be a disease, a "strange etherial entity", or some physical event that the protagonists need to overcome like a "rift in space" or some such. Such villians are (regrettably) often poorly written, but beyond that, non-human villains tend to wear kind of thin.
Stories here are typically presented in a "whodunnit" format, where characters have to use their scientific knowledge to figure out puzzles. As such, it is often a chance for authors to show off how much they know about physics and astronomy. (And likewise, a chance for the discriminating reader to point out trifling logistical flaws or inconsistancies.) This is a good platform for doing time-travel stories, which can be lots of fun.
On some occasions, however, this genre can be a good platform for discussing philosophical issues that we might confront in the distant future. An example of this is human-alien relations, the feasibility of a utopian society, or the rights and personalities of clones. Perhaps the most deeply explored sci-fi philosophy surrounds the theory of artifical intelligence: How do we determine when a robot becomes intelligent? What rights would such a robot have? Asimov delved extensively into this issue in his "Robots" series ("I, Robot", "Robots of Dawn", etc.).
TV Shows: Star Trek (TOS, TNG, DS9, Voyager), Dr. Who, Buck Rodgers, Battlestar Galactica, Red Dwarf (parody television series),
Books: Hitchiker's Guide to the Galaxy (parody books), The "Robots" series by Asimov.
(Note: The appearance of parody stories and shows like Hitchhiker's Guide and Red Dwarf demonstrates that this genre (and the collection of futuristic genres) is maturing and becoming more widely accepted.)
This is basically "mythology gone futuristic". Some have referred to this genre as "Space Opera".
This genre will typically have most or all of the elements of Classic Sci-Fi, with an occaional dose of some of the elements of the 'Space Thriller' genre.
What sets this genre apart from Space Thriller & Classic Sci-Fi is the presence of some kind of "magic", "psionics", or "willful force". In Star Wars there is The Force, in Babylon 5 there are the "Teeps", in Dune there are the "Mentats" and the "Bene-gesuit Witches". Along the same lines, in Space Fantasy, you will typically see more "traditional" weapons like the light sabers in Star Wars or the daggers in Dune. Often, this magic will supplant or replace many of the "high-tech" gadgets found in Classic Sci-Fi.
Another thing that sets this genre apart from the others is the story content. See the 'Platform' section below.
As already mentioned, many of the same characters from the previous two genres are found here. What you will find here, however, is that a number of the characters (or even whole races) will take on "archetypal" roles. For example, occasionally you will see an appearance by some "benevolent" alien race, which is very distant, cryptic, and occasionally helpful (i.e. Vorlons in Babylon 5). This character / race kind of fills the Mystic-Master / Mentor role often found in many traditional stories (i.e. Yoda / Obi-Wan).
Space Fantasy stories are often nothing more than traditional fairy tales / hero stories usually with some spying / political intrigue thrown in for good measure, and placed in a futuristic setting. As such, you will often find an "epic battle" (i.e. the Shadow Wars on Babylon 5), a "hero quest" (Luke Skywalker and the Jedi way), a "people to redeem / lead" (Price Atradies leading the Freemen in Dune), or a "tyrant to slay" (Flash Gordon vs. Ming the Merciless).
This does not mean to say that writers won't use robots, communicators, or warp-fields in interesting ways, but they aren't meticulously explained. Therefore, the elements of Classic Sci-Fi are used, but with less attention paid to all the 'hows' and 'whys'; they're just story elements, nothing more.
In a nutshell then, here's the litmus test: If you could convert ray-guns to crossbows, the space ships to boats, and the space stations to castles, and the story remains largely intact, you've got Space Fantasy.
Movies / TV Shows: Babylon 5, Star Wars, Flash Gordon, Logan's Run. Deep Space Nine will occasionally have elements of this, Star Trek II: The Wrath of Khan is a fine example
Books: Dune, The Foundation Saga by Asimov (and others),
Contributed by Daniel Pryor (with some small editing by me)
These are movies, books, etc that take place in the future but retain the same laws of physics that we currently understand. 2001 would be a good example of this. As a matter of fact any of Arthur C. Clark's work falls into this category. There are other authors that also would fit here. Ender's Game also uses real-world physics, but maybe the bug thing pushes it over.
The main thing that sets this apart from "Classic" SF is that it is scientifically based. No pseudo-science like wrap-drives and phasers.
Just humans. Sometimes computers will be interactive and somewhat intelligent, but you rarely see anything as involved as independant robots. HAL in 2001 is a good example of an intelligent computer.
This genre usually is involved with discovery or exploration. Some discussion of "The Monument to Man's Achievements" (i.e. walking on the moon) is typically heard.
Movies: Gattaca, The Andromeda Strain, Silent Running, 2001 / 2010