Punctuation
Though in the English language there is no standard accepted method to denote irony or sarcasm in written conversation, several forms of punctuation have been proposed. Among the oldest and frequently attested are the percontation point—furthered by Henry Denham in the 1580s—and the irony mark—furthered by Alcanter de Brahm in the 19th century. Both of these marks were represented visually by a ⸮ backwards question mark (unicode U+2E2E). A more recent example is the snark mark. Each of these punctuation marks are primarily used to indicate that a sentence should be understood at a second level. A bracketed exclamation point or question mark as well as scare quotes are also sometimes used to express irony or sarcasm.
In certain Ethiopic languages, sarcasm and unreal phrases are indicated at the end of a sentence with a sarcasm mark called temherte slaq, a character that looks like an inverted exclamation point ¡.
In subtitling for the hearing impaired, sarcasm and irony is often shown by the use of the "(!)" icon.
Read more about this topic: Sarcasm