This article was originally written a couple of months ago for the Surreal Game Design blog, which is currently deceased. I'm publishing it here instead.
I know what you're thinking. Let me guess. I can see it on the tip of your tongue. What the hell is a trope? Is this British lunatic making up words again?
A trope is a kind of story-telling shorthand. Camera cuts are tropes. Camera dissolves are tropes. The good guy in a Western riding off into the sunset at the end of the movie is a trope. The nerdy guy getting the girl by the end of the teen movie? That's a trope too.
They're like memes, but instead of being Just infectious ideas, they're specifically memes that relate to how a story is told. The only other meme with a given name I've ever come across is the ear worm.
The really cool thing about tropes (other than the information they convey) is that unlike most industry short-hand, they actually have cool names. I mean, where else are you going to come across a camera move called "The Khan"? (Although it should really be spelled The Khaaaaaaaaaaaaaaan!)
Of course, video games have their own particular brands of tropes specific to them. After all, once you have a new story-telling medium, it suddenly accrues tropes like barnacles. The one everyone has heard of is "Crate Expectations", and it's now a sport to rank games on the amount of time you have to play until you hit the first crate in the game.
Why do we like tropes?
Well, for a start, once they become embedded in the media, you don't have to think about them any more. You don't think about hitting the Start button to pause your game... and nowadays, all kinds of things can be expected to live in the start menu - like your current list of objectives. That's a trope too.
Not only are they a useful user interface tool, but they push the medium along. Look at an old movie from the 60s. (Sorry, film students... I'm going to pick on Citizen Kane and 2001: A Space Odyssey now as specific examples). They're shit. Well, okay, maybe that's a bit strong. They're not shit. They exemplify the inherent beauty in the medium, and they were stellar works for their time... but the medium has moved on. They're now boring as all hell, and no matter how emphatically anyone whispers "Rosebud" into a boom mike, and no matter how many candles of lighting you throw at it to make it have the largest depth of field ever imaginable (even if the actors get all squinty), I'm still going to only get 15 minutes into the movie at the end of the day before I get bored and turn it off. As for 2001, let's face it, you're only going to watch it for the end these days, and there's only so many times you can watch that without getting so completely mindblowingly high that you start trying to sync it up to Dark Side Of The Moon.
The medium has moved on. We learned the short-hand. And once you know the short-hand, you don't need the long version any more. Everything these days is fast paced Jerry Bruckheimer cuts and always starts in media res. In fact, some media relies on tropes for its effectiveness. Spoof films like Airplane, for example. Horror movies pretty much require them - you just don't get that "Don't go in there!" feeling unless you've seen how it goes down when they walk through that door a million times before.
Where things get interesting is when a new trope hits and spreads like wildfire. The rage flashes in The Suffering were a horror videogame trope that hadn't appeared before in the medium (although they'd been used in other places in film before). Possibly the most well known new camera trope in a long time has to be the Bullet Time sequences in The Matrix movies (which then quickly jumped the divide and started showing up in video games as well - heck, Stranglehold even called it Tequila Time). Michael Gondry had previously tried to get the ball rolling with a number of music videos along the same lines, and then The Gap commercials writ it in stone, but it took The Matrix for it to become a trope. And now it shows up everywhere - even in animation where frankly, it's not even that flashy because... well.. it's animation, and you can do anything you like in animation, just by drawing whatever you want to see.
So what's the brand new trope I care about right now?
That'd be something I just saw in Call Of Duty 4: Modern Warfare. And I'll talk about it in my next (hopefully much shorter) post.
(Crate photo stolen from tvtropes.org)
 Which brings me right back to the earworms... but I digress.
 Spoiler Warning: It's the sled. The sled is called Rosebud.
 Jerry Bruckheimer cuts are cuts which last no longer than 5 seconds. Watch any Bruckheimer movie, and you'll see that none of his cuts last longer than this. It's what makes them chock-full of actiony stuff.