Under what circumstances is someone likely to use the chat abbreviation, "IYKYK"?

IYKYK stands for "If you know, you know." It would most often be used for a situation where someone who has experienced a situation would understand. Maybe it is knowing what it is like only having a black and white TV and only having 3 channels which is something kids these days would never understand. Or maybe life without the internet. The acronym has become popular on Twiter and other social apps.

Simply, IYKYK stands for the phrase, ‘If you know, you know.’ It essentially refers to a reference or throwback that only certain people will get, though that group of people depends entirely on the context.

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