What is that 4th wall you ask? It's hard to define, harder to imagine. Most of the time you don't even realise it's there. If it's a wall it's like one of those invisible Star Trek force field walls, the kind that sort of raises the hairs on the back of your neck when you're entering it, just enough to make you think something's hinky, sending cascading waves of regret about being the one twerp laden with a red shirt. Did Kirk just give you a thumbs up? You'll want to retort with a middle finger.

And when you try and walk out of it you encounter the invisible force field.

But it would be something larger than a small boxed cage, perhaps like the Truman Show, you're the inhabitant of some massive elusive domed studio where you're mostly content, oblivious to the confines of your television. It's not often that the 4th wall is broken, not often when gaming makes that clever jump where it references reality, or when it so convincingly turns and winks to the player to let you know - yes you are in on the joke.

In my gaming life I can only say it's happened a scant few times and only enough to be memorable in a small number of cases.

The first would probably be in Lucasarts' sublime and hilarious graphic adventure game Sam and Max - when you would click on a character to see if they have any useful information for you. And instead of the same, stock answer repeating, telling you nothing, a conversation took place, with the character coming up with more hilarious answers each time. Even going to the extent of questioning your intelligence and telling you that it doesn't matter how many times you click, the game won't help you. It achieved that 4th wall break through gentle, grin worthy mockery.

Some of you gamers who entered the fray in the Playstation 1 era may remember a particular Metal Gear Solid boss, actually fiddling with your gamepad and memory card - in a massive asshole move. When most games are trying to immerse you into a gameworld, here was a moment telling you: you ARE playing a game - we know it, you know it, so let's have some fun, and boy, did we?

2002 brought a chance for the now defunct Silicon Knights to present us with sanity effects, if you never played this game, as you lost health you lost sanity and things in the gameworld started changing. At one point the game made it look like it was deleting your memory card, oh how funny it was, almost having a mini-heart attack when it happened. Talk about survival horror, my eyes were popping out of my head like poor old Arnie at the end of Total Recall.

And now onto the Wii U - well let's start with the Wii first shall we - the little guy, the cheap guy, the guy with dated clothes, unkempt hair, with an old cell phone too, but with bags of personality. Like a wacky inventor in the back of his shed, he would probably look something like "the Doc" from Back to the Future and tell you something about reaching 88 mph and wearing shades, before handing you a hovering skateboard, or Wii Balance board shall we say.

Hardly at the cutting edge of processing power, it's innovation in the controller realm has actually brought out the biggest and best 4th wall breaking moments. But it's not the tennis racquet or sword waving I'm talking about here. If it's not directly mimicking motion, it was doing something else. That something else is what this fumbling writer is aiming to describe to you and congratulations to anyone still reading. You're all well read, manly and dedicated to the cause.

So heard it is, sound.

Whilst most dictionary definitions of the 4th wall would be the gap between fantasy and reality, I would describe it as the gap, the moat if you will. Your television is the castle, the gap between you and it, is the moat. And there you are on the outside looking across the moat at a castle you'll never actually enter. As my overlong prelude explained, you often don't notice until that wall is broken. But when it does it's so rare and delicious you savour that taste and crave even more.

For me the unchampioned use of the Wii controller was the speaker embedded into the remote. In rare games like No More Heroes or Silent Hill Shattered Memories you would receive or make phone calls and the audio would play from the wii remote speaker. Big whoop! LOOK AT MY HD VISUALS PEASANT

To that spurious ill mannered buffoon I would say hush, quiet down a moment, press that speaker close to your ear, with the volume so low you would have to press it to your ear. Suddenly that gap between you and the castle was breached as a long invisible arm clawed you into the gameworld. You're not safe there, you know? - the game would tell you, you are a part of this, you cannot escape. The tinny, sometimes crackling quality of the Wii remote speaker would only add to the atmosphere and it could be incredible. If the television audio is like putting your phone on speakerphone, getting a message on the Wii remote was like getting a personal call.

Only you could hear it, it was only for you, the gamer, it prodded a finger in the centre of your chest and drew you into the gameworld in a way you just cannot do in other ways. And so we move onto the Wii U - what happens when you now have dual speaker audio clarity on the gamepad, as well as video and touch screen functions too? Those who were there for launch will remember the hardcore gamers badge of choice: Zombi U.

Ubisoft ran wild with Wii U functions and at the top of the list was the audio. In the game a disembodied voice of a mastermind surviver rasped through the speakers of the gamepad. At its best, the gamepad becomes a survival kit, a toolkit if you will, a gadget. Ubisoft used the speakers for the Preppers instructions and crazed monologues, and his voice would crackle through the gamepad like a handheld radio. It was personal too, the Prepper was talking to you as a survivor, the intimate voicings would sometimes whisper, the voice coming through that radio in hushed whispers - if you make too much noise "they'll" hear it too and you'll be neck deep in your own blood. The game became personal, not only existing on the screen in front of you but also right in front of you, so close you could almost feel his hot disgusting breath on your face, you could almost imagine him with a knife at your throat, croached behind the sofa like an evil Sam Fisher.

The same can be said of receiving video calls in Lego City, it's really hard to be immersed in such a deliberately ludicrous world, but the video calls and audio coming from the gamepad you take for granted and you only miss it when it's missing. Which brings me onto Deus Ex Human Revolution. How cool would it be for communications to come out from those speakers? Alas you can understand why the little animated head and voice are on the main screen, the second screen is so packed with gamepad functions adding something else over the top might become intrusive.

Thankfully Deus Ex breaks the fourth wall in another way. In Deus Ex you play as a mechanically enhanced human and the gamepad becomes an extension of you, when you're prowling about on the main screen the gamepad is sucking you in like the hooker in Police Academy as you observe your digital display. It makes you feel like a spy with a high tech gadget in your hands. But what I most like about it. The silliest, almost insultingly simple function of the gamepad - one I feel almost pained to admit that it worked on me..... is..... reading emails/articles/ebooks on the gamepad touchscreen.

Hardly groundbreaking in concept, it's actually a delightfully devilish treat. It functions much like a modern tablet and this is where it becomes relatable and believable. It's so difficult to explain the feeling, that part when the gameworld hidden behind that television suddenly jumps 2 feet in front of your face, but it's real, it's tangible and it's so immersive. So hats off to the Wii U gamepad, if anything it's successful in that one respect: the crossing of moats.

Let's go save that Princess eh?