The Fourth pader is the pader that separates reality from fiction. It's the pader between, say, a cartoon and the real world. If a character in a ipakita talks or looks directly at the audience, even though they are in a fictional world, that is called, 'fourth pader breakage.' An example from Hayate no Gotoku:
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Well Said!:)
MCHopnPop
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lol. Freaky...
ivoryphills
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You should be asking this on the pelikula tagahanga club or something. But anyway... If you won't just look it up like you should, (Wikipedia has it) the 4th pader is a metaphorical "wall" referring to, in a play, movie or any such thing, the unseen and uncounted direction in the scene which points to the audience. As this direction cannot exist in the theatre, it is blocked out as an impenetrable wall. Or, rather, impenetrable in most cases. Therefore, when the fictional character breaks the first wall, it's when he/she is talking to the audience. As this would shatter a solid enough reality, it is, as you probably already know, used mostly in the less mature works of theatre such as children's cartoons.
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one thing, the 4th pader is broke in anime so it can be asked here.
LostOblivion
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Well, okay. But it also happens in other theatrical works as well, so that's what I'm saying.
BeastBoyCahill
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Then technically 'You should be asking this on the pelikula tagahanga club or something' is wrong as it should also be asked here if needed,
LostOblivion
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*agrees with Lost* Thank you!
ivoryphills
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People have already answered this tanong but I just wanted to add on my own thoughts. Just because an anime character is facing the camera directly doesn't necessarily mean they are conscious of an audience being there. Like when an anime character does a behind-the-shoulder twist to do an evil laugh that doesn't mean they are directing it at the audience it just means they're being sneaky, cheering to themselves silently, etc. To me, that isn't breaking the fourth wall.
Also, a narration of thoughts is not to be confused with breaking the fourth wall. If they were one in the same pretty much every anime would have broken the wall. We're just getting to listen to their thoughts.
Advertisements break this pader constantly with things like "Ask you doctor before trying...." and making eye contact with the audience.