Question mark
The rhetorical question mark or percontation point was invented by Henry Denham in the 1580s and was used at the end of a rhetorical question; however, its use died out in the 17th century. It was later revived in modern-day society by Matt DiRoberto. It was the reverse of an ordinary question mark, so that instead of the main opening pointing back into the sentence, it opened away from it. This character can be represented using the reversed question mark (⸮) found in Unicode as U+2E2E. The percontation point is analogous to the irony mark, but those are even more rarely seen.
Inverted question and exclamation marks
The inverted question mark was adopted long after the Real Academia's decision, published in the second edition of the (Orthography of the Castilian language) in 1754 recommending it as the symbol indicating the beginning of a question in written Spanish—e.g. ("How old are you?"). The Real Academia also ordered the same inverted-symbol system for statements of exclamation, using the symbols "¡" and "!". This helps to recognize questions and exclamations in long sentences. "Do you like summer?" and "You like summer." are translated respectively as and (There is not always a difference between the wording of a yes–no question and the corresponding statement in Spanish.) These new rules were slowly adopted; there exist 19th-century books in which the writer uses neither "¡" nor "¿".