You know that time has marched on when something that everybody did without really thinking finds itself categorised and pinned down by a catchy title. Take "emergent gameplay", for example.
Today, that's the fancy game theory term for players mucking about and making up their own rules, regardless of what the designer intended. In the eighties, that was just how we rolled, yo.
Maybe it was because so many of us were playing from hooky C60 tapes copied off a mate, or maybe it was because we just couldn't be arsed to read the two paragraphs of instruction on the inlay, but I'm convinced that most gamers of 20-odd years ago often had only the vaguest idea of what the goal of their favourite games were.
That was certainly the case for Turbo Esprit, Durell Software's hugely ambitious free-roaming car chase for the ZX Spectrum. It's a game with which I spent many happy hours without ever really knowing or caring what I was supposed to be doing.
Turbo Esprit still impresses in 2011. This is a 3D driving game set across four fully mapped cities, each packed with naturalistic details such as pedestrian crossings, roadworks, one-way streets and persistent traffic that actually follows the Highway Code and doesn't simply vanish once it's off screen.
All this is squeezed into 48k, a smaller file than you'd need for a JPG of the game's cover art. It's simple and rudimentary by today's standards, of course, but favourable comparisons to Driver and Grand Theft Auto, Esprit's genetic descendants, are as obvious as they are deserved.
Having picked a city from the four on offer (Wellington, Gamesborough, Minster and, er, Romford) you're free to roar around the wireframe streets at will. Roar, of course, being a relative term. As forward-looking as the game was, sound design is not an area where it excels.
The theme tune is a classic, a jaunty whistle-along number that has lodged in my brain for 25 years, but in-game the mighty Lotus was reduced by the Speccy's farting sound chip to little more than a series of clicks and quacks, like a duck being beaten to death with a Geiger counter.
None of that mattered. Nor did it matter that there wasn't really anywhere to drive to. You could go wherever you wanted, travel the wrong way down one-way streets, knock stick men off ladders and shoot your way out of dead ends by turning your machine gun on the queue of constantly spawning civilian cars blocking you in.
You took penalty points for civilian slaughter, but since hardly anybody knew or cared what the points were for, that didn't matter either. It was a pure a sandbox as it's possible to imagine.
Control-wise there were some clever ideas. As well as shooting your gun, the fire button doubled as a handbrake. When it was pressed in conjunction with left or right your sleek sports car would hurl itself in the required direction.
Do this at the correct moment as you thundered through a junction and you'd instantly slip onto the new road without losing momentum. Get it wrong - as you invariably would - and you'd end up lodged horizontally across the street and forced to perform a laborious three-point-turn or, worse, you'd die instantly in a squelchy red fireball.
Turbo Esprit was produced with "technical assistance" from Lotus, though this was clearly a far cry from the exacting demands of todays relationship betwixt videogames and sports car manufacturers. The famous eighties vehicular icon looks more like a bar of soap on wheels and explodes at the slightest provocation, presumably not the thrilling endorsement the company was hoping for.
Even so, in an era when I considered Street Hawk to be the pinnacle of televised entertainment, Esprit's mix of navigational freedom and Russian roulette cornering was more than enough to scratch my gaming itch.
Every now and then I'd catch glimpses of the objectives I was supposed to be tackling, occasional spurts of colour in a two-tone world. But it never seemed as much fun as the anarchic fannying about I was already enjoying, so they remained mysterious.
The aim of the game, in actual fact, was to roam the streets looking for a gang of drug dealers. Text updates from HQ were meant to direct you to a specific map reference where the nefarious peddlers could be found.
Some five years before Tarantino, the crims even had their own colour coding. The car carrying the initial supply was red, the delivery cars were blue and roving hitmen patrolled the city in bright pink cars, clearly the game's equivalent of Steve Buscemi.
They had a fairly sophisticated network going on. Your targets weren't simply pootling around at random, but following specific routines that you had to decipher and disrupt in order to succeed.
Supplies would arrive at their intended destination, then delivery cars would set out to make the drop. Once they'd done their dirty deeds they were gone - and you'd failed. Even then, the game let you carry on, killing time (and pedestrians) until more drugs arrived.
It's a surprisingly stiff challenge. In fact, firing Turbo Esprit up today, it's clear that playing the game properly is often borderline impossible. Narrow streets and randomly spawning vehicles on the other side of the road making overtaking a deadly gamble.
As such, reaching the drug cars on the map before they vanish relies is as much a matter of luck as judgment.
It's also easy to get lodged on corners if you take them too early, forcing a complete restart. And as civilian cars can box you in and never move you have to destroy them, racking up penalty points if not guilt.
What I love most about Turbo Esprit is that I was blissfully unaware of all this intrigue and inconvenience at the time. I played it endlessly. Even though I had the original cassette in its robust Durell clamshell case, complete with instructions, I somehow neglected to understand the core premise of the game for my entire childhood.
To me, Turbo Esprit was simply the "drive really fast around a city" game. At that, it excelled.
Even better, to my 10-year-old sister, it was "Picking My Daughter Up", a game that gave her the chance to live out the giddy dream of being a suburban mum on the school run.
OK, so pink cars would occasionally turn up and try to shoot her, but this never seemed to bother her. I still wonder how my sister rationalised these sporadic drive-bys into her domestic fantasy. Maybe that's just what happens in Romford.
That she was able to co-opt a violent fast-paced crime game and turn it into something that appealed to her less visceral tastes is rather brilliant, though, and a fact that still amuses me to this day.
Ultimately, and much as with other pioneering 8-bit Britsoft classics, whether or not we knew what we were doing didn't really matter. Either by accident or design, Turbo Esprit hit on one of the key principles of video gaming. Namely, that telling the player how to play becomes a lot less important when the game is simply fun to play with.
It was easier in the eighties, of course, when we were just grateful for the ability to move blocky shapes around on the telly. But you can still see that ethos, lurking close to the surface of today's most popular open-world games.
Give us something to do and we're happy. Give us the space to do something of our own and we fall in love. And I still love Turbo Esprit.