The useless, random shit that a computer or other electronic device spits at you when it thinks it can display foreign characters that it really can't.

Extra points awarded for when mojibake is spotted on digital billboards, electronic signage or even ATMs.
Tim Westwood settled in to a cosy evening of checking out his Wikipedia article, only to find some anonymous asshat had replaced it with a dollop of j-pop mojibake.
by signwave February 12, 2009
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