It is a real term, and I've seen it used enough to where I can distinguish between people and peoples without having ever looked up a definition <_<
It's like when you're talking about group and groups. Group refers to more than one, but it's treated as singular because you're talking about the entire unit, of which there's only one. And if there's more than one unit, it's groups.
Same thing with people. It refers to multiple.. uh... persons, but since you're talking about the persons as one unit, it's singular. And if you're talking about multiple units, it's plural.
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"Duel audio? You mean like rap battles?" - termina_rzident
KrahenProphet and Kana are on opposite ends of the Awesome Spectrum.