There were just plain punks, of course. Still are, probably, if they can sufficiently distance themselves from Vivian in the Young Ones. The iconic hair and attitude are memes that has survived the actual subculture's descent into the voracious jaws of commercialism (1). Especially the attitude, and the curious legacy it left in the nomeclature of science-fiction and fantasy literature (2).

There are lots of punk genres, but the original is the cyperpunk — a genre defined by obsessive technology combined with a dystopian, even nihilistic attitude: Gibson, Sterling, Bethke (who coined the phrase). I'm not going to reel out a brief history of cyberpunk here, but the two points above are very much the poles that the genre's washing ishung from. The technology is key — notwithstanding strong storylines and strong characters (and I've eulogised Gibson, particularly, before), the stories are generally about the technology — take the tech away and the story can't work. The grimness of the world supporting such technology is generally one of corruption, crime and corporations. There are few absolutes, few genuine heroes, few nice guys. Film has tried the genre with differing success. Blade Runner is a good example (3). Interestingly, although the textbook cyberpunk is set (a) on Earth and (b) in the relatively near future, it's entirely possible to have a far-future hard sci-fi cyberpunk — Morgan does it with Altered Carbon, for example, and a lot of Neil Asher has that kind of feel as well.

But what if you want the punk without the cyber?

The name, once tapped on the anvil and found to be pure (4), has spawned numerous spin-offs, and indeed there is a tendancy to coin a new subgenre for any given book: pick a concept and add "punk". Certainly, there should be a word for Mary Gentle's historical-magical Rats and Gargoyles, which is set several hundred years too early for Steampunk, but definitely has a lot of the punk to it (5). Thaumatopunk, perhaps? The possibilities are endless. One of my favourites is "Mannerpunk", used bizarrely to desribe the sort of social-interaction fantasy that is set in an imaginary world but frequently lacks even a mention of magic. The key example of this is Gormenghast, although what Peake would have thought of the word I have no idea. Still, the little thread of a genre keeps going. Hardinge's Fly-by-Night is more of a Mannerpunk than anything else, and I'd even make a case for Clarke's Jonathan Strange and Mr Norrell even though that has magic to spare. But then we're starting to talk about alternative histories…

So, Steampunk, then, surely the most influential and prevalent of the post-cyber punks. Also maddeningly difficult to actually pin down. As Empire in Black and Gold and the rest of the Shadows of the Apt sequence have distinct Steampunk features, I should really be able to say what makes a punk steam (6). Bafflingly, the term was invented by KW Jeter to describe the sort of work that he, Blaylock and Tim Powers were producing, in the latter's case specifically The Anubis Gates. Now I'm a great advocate of Powers, and yet nothing in The Anubis Gates or much of the rest of his work is anything like the steampunk genre that most people would actually recognise. Having made this bold statement, what would I put forward as the basic axioms?

- airships! lots and lots of lovely airships!

- Victoriana — whether it be the actual British Empire, Gawd bless 'er, or some surrogate: imperial expansion, a golden age of peace, prosperity and ruthless exploitation, workhouses, Dickens, the East India company, the rich/poor divide, all that stuff.

- a 19th century-styled technology far beyond the actual, and yet stylistically based on it: steam, gaslamps and clockwork can accomplish anything, up to and including the conquest of interstellar space.

- an abiding interest in inequality, deprivation, poverty, racism, greed and social injustice — the punk to the above-mentioned steam.

- usually, although not always, an urban setting.

Powers, for example writes in a real-world historical setting. Steampunk, as commonly understood now, is at the least altnerative-history, and often complete fantasy. The technology, especially, is almost-uniformly (7) impossible, often ill-defined or muddied-over by invented concepts like Cavorite or Phlogiston that perform whatever feats are requested without ever having to explain themselves. As long as it sounds as though Verne or Wells would have come up with it, that's fine.

However, this vaguary of technology has an unusual and beneficial spin-off. The writer knows it wouldn't work. The reader knows it wouldn't work. Therefore the steam is not the focus of the story in the way that the cyber is of cyberpunk. There's no point having a plot turn on some technical nicety of your machine, when the machine itself is held together purely by fudge and good will. But this has become, I'd argue, a strength of the genre.

Steampunk, then, gives a setting, and not a focus, and so the stories get a great deal of freedom within that setting. As for the setting itself, there is something irresistable (to me, anyway, and evidently many others), about the whole decayed victoriana, the empire propped up by fantastical mechanism, the ennui of the rich, the  nigh-slavery of the poor, the graceful bulk of an airship, the clean turn of the gears, the hiss of the boiler: Stephenson's Rocket become a world-striding behemoth. All this is dressing, though, to decorate the plot. The plot is whatever you want it to be

To name a few: Northern Lights has Pullman's other-Oxford, his demons, his church and inquisition, his soul-dividing machines. Foglio's Girl Genius is tremendous fun, classic extreme Steampunk with giant robots, mad scientists and other-worldly alien invaders. Alan Campbell's Scar Night (and recent sequel, Iron Angel) match up the genre with gothic horror, another (particuarly nasty) inquisition and one of fantasy's most insane cities, and unlike the two aforementioned is entirely within a seconary world, rather than an alternate one. The same also goes for Calenture by Storm Constantive, hosting several strong contenders for the all-comers maddest city championship, which by some lights at least is a steampunk. Oh and I could go on — Reeve's Mortal Engines, perhaps, and I've surely already rhapsodised about Perdido Street Station and its sequels, Mieville's tour de force of high fantasy social satire — but also arguably a steampunk masterpiece. The genre is extremely elastic, in a way that cyberpunk is not, and it all stems from the fact that, at heart, nobody's pretending that any of it could work.

And so, with steam power comes a freedom that the nanomachines and wired reflexes of cyberpunk deny us, and this freedom is almost always used to focus on the punk end of the equation: the unjust society. Whether it's the Magesterium of Dark Materials, Mieville's hideously venal New Crobuzon government, the religious tyranny that dominates Campbell's city of chains or, dare I submit, the wretched factory workers of Helleron in Empire, Steampunk settings seem to be an unparalleled opportunity to explore social wrongs.

Why? We ourselves live in a world that grew from seeds set down in the industrial revolution and ardently watered during the 19th century, whether those seeds are the locomotive or the spinning jenny or the limited liability company. If. at some point between that revolution and the Great War, the author inserts a key into time and unlocks the entire course of history from that point, then whilst technology may reach some never-never golden age of steam, we seem to find that society remains dragged down by its woes, that the bad gets worse, and the good attenuates — and this is just as true for a secondary as an alternate world: the phenomena is keyed to the sort of society required to support that level of technology. Freeing history that late in the day precludes utopias, and so the writer has the double-benefit of being able to build any manner of fantastic world out of the meccano of pistons and gears, whilst retaining that most elusive element of fantasy fiction: relevance.

(1) Reminiscent of Withnail & I, "They're selling hippy wigs in Woolworths." Not that, outside of the Young Ones, hippies and punks would have had much to say to one another, but both went the same way into the gullet of capitalism.

(2) This paragraph brought to you in as high-falutin' a manner as possible, for your reading pleasure.

(3) Some people would claim The Matrix but I'd argue against it being  cyberpunk at all. The cyber is there, but the punk went down the drain with the rest of human civilisation, and what's left is something more like "cyber-survivalist", a splinter genre that would neatly fit Terminator as well.

(4) An ideal metaphor when talking about cybertechnology, I thought.

(5) And the third novel of the series, Left to His Own Devices, is genuine cyberpunk.

(6) Stamp on his toe.

(7) almost-uniformly? What cop out is this? And yet if I said "uniformly" there would surely be some scientifically-realised steampunk setting out there sending clockwork spaceships to the canals of Mars based on absolute and indefatiguable logic, so I'll cover myself.