Although in the written English language there is no standard way to denote irony or sarcasm, several forms of punctuation have been proposed.
Irony Mark
Among the oldest and frequently attested are the so-called percontation point invented by English printer Henry Denham in the 1580s, and the irony mark, furthered by French poet Alcanter de Brahm in the 19th century.
Both of these marks were represented visually by a backwards question mark. The character can also be represented on Windows by using the Alt code 1567.
These punctuation marks are primarily used to indicate that a sentence should be understood at a second level. A bracketed exclamation point and/or question mark as well as scare quotes are also sometimes used to express irony or sarcasm.
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