But does it really? Leaving aside types of fantasy with more modern-style settings, is fantasy technology really such an oxymoron? We tend to think of technology in terms of the recent — computers, jet engines, nuclear power stations and the rest — or what we might have in the future, such as warp drives or matter transportation. We might stretch a point to include devices from the age of steam, but no further.
But that's misunderstanding what technology is. A water-mill is technology; a suit of armour is technology; a plough is technology. Hell, even bashing two rocks together to crack nuts could be regarded as technology. The most successful piece of technology ever invented is arguably the wheel — though the plough might give it a run for its money.
Whatever kind of world you might create, it's going to have technology of some kind, and that means the technology is going to have to make sense. Inventions aren't made in isolation; sometimes you can't have one thing without another. The light-bulb (the one fantasy writers won't change) couldn't have been developed before the later 19th century, because it required a near-vacuum inside and depended on the development of high-quality vacuum pumps.
This kind of thing goes on all the time. One of the most persistent misunderstandings about the ancient world is the belief that the Greeks invented the steam engine, but were too otherworldly to realise its potential, but that misrepresents them.
The first known steam engine was invented by Hero of Alexandria in the 1st century AD. Called the aeolipile, it was a device that used pressurised steam to make a sphere rotate. No records survive of it being put to practical use, but it's unlikely that this was pure otherworldliness. Others of Hero's inventions, such as his force pump, were used, as were many inventions of the Greek world. Archimedes's famous eureka moment is often seen as a breakthrough in pure physics, but he was actually addressing a very practical problem, while his irrigation screw was so successful that it's still in use for some purposes.
The Greeks were actually a highly practical people, and the Romans even more so. So why didn't they see the potential of the steam engine?
The answer is that steam production requires huge pressure, and the materials need to be strong enough to withstand this pressure. The reason steam power became a practical option in the Industrial Revolution was that metallurgy had reached the point that steel could be made strong enough to do the job. Hero had to make do with inferior iron which, though it would do for occasional demonstrations and "miracles", would have exploded if the aeolipile had been used on an industrial level. Perhaps it did.
There's a number of these myths about technology in other cultures, especially China. The Chinese came up with printing long before Europe had it but, we're told, it took Gutenberg to think of using movable type. Well, not quite. The Chinese did develop movable-type printing, but it just never caught on.
This is because of the difference between the writing systems. A European printer needed, with upper and lower case, numerals and punctuation, perhaps seventy or eighty drawers of blocks (a big drawer for e and a rather smaller one for q). Chinese script has thousands of symbols. Although systems were developed to make the blocks more accessible, it just took too long. In that time, you could have etched a whole plate and been on to the next.
A rather different misunderstanding applies to the Chinese use of gunpowder. Again, they had it long before we did, but supposedly only used it for fireworks, leading some people to regard them as naive, others as more civilised than us. Actually, by at least the 13th century, if not before, Chinese armies were equipped with bombs and ballistic rockets, and even had a device for launching multiple rockets simultaneously. The only thing they didn't manage to come up with was the gun as a means of delivery.
These examples illustrate three of the main elements that control what technology a culture might or might not have: the state of the supporting technology, cultural necessities, and mere chance — whether anyone happens to think of the idea.
Even if you're presenting a primitive culture where some genius has come up with the concept of the wheel, the invention will rely on whether he or she has the tools to create a circle of wood. Or the idea might be there (from using logs as rollers, perhaps) and the challenge is to develop tools and products at the same time.
Technologies affect one another in many ways, and this is especially true in the technology of warfare. In the mid-mediaeval period, for instance, when the cutting-edge weapons (erm, sorry) were the sword, lance and mace, chain-mail armour was good enough to give a knight a sporting chance of survival. Crossbows were more deadly, but they took too long to reload to be a serious problem.
The armourers fought back, developing plate armour that was both light and tough, and this (along with Joan of Arc's inspiration) played a large part in the eventual French victory in the Hundred Years War. Even this new armour, though, wasn't a match for the hand-held, anti-personnel guns that emerged. Through the 16th and 17th centuries, armour became increasingly more irrelevant, and was eventually abandoned.
Technology is a vital part of world-making, and it needs as much thought and research as anything. Of course, unlike the "harder" forms of science fiction, fantasy offers plenty of short-cuts and cheats, and it's sometimes possible simply to create an alternative that doesn't have the same requirements. You want artificial lighting in a society too primitive to have sophisticated vacuum pumps? Just call it a glow-globe, and imply that it doesn't work the same as a modern incandescent light-bulb.
And, of course, there are always the standard fantasy get-out-of-jail-free cards: It's the product of magic, and no-one understands how it works or I know it doesn't make sense, but the god who created this world ordained it so.
On the whole, though, it's far more fun if your world makes sense. That means that the technology needs to make sense too, whether it's a cart, a suit of armour, a ship or a light-bulb.
So, how many fantasy writers does it take to change a glow-globe?
(Light-bulb by Trixyrogue)