An interrobang is a seldom-used, non-standard punctuation mark that combines a question mark and an exclamation point. It was invented in 1962 by Martin K. Speckter, an advertising executive and editor of a magazine called Type Talks, to fill a gap in punctuation (particularly in advertising headlines) in which neither an exclamation point nor a question mark could fully convey the writer's intention. He came up with the interrobang to indicates an exclamatory or rhetorical question, such as "Can you believe that?!"
Found on TypeTalk.
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