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About
Interior Monologue Captioning is a type of image captioning that is used by randomly dispersing text on an often unrelated image to reflect what the subject is thinking or feeling, often using Comic Sans font. The captions are mostly, if not always, used to achieve comedic effect. Most of the time, the words used in the caption are misspelled and poor grammar is used in them, adding to the comedy.
Origin
[Researching]
Not much is known of the origin of this meme, but it is generally accepted that it started on the social mircoblogging site Tumblr.
