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.
Looped square
The looped square (⌘) is a symbol consisting of a square with outward pointing loops at its corners. It is referred to by this name, for example, in works regarding the Mississippian culture. It is also known as the place of interest sign when used on information signs, a practice which started in Finland in the 1950s, spreading to the other Nordic countries in the 1960s. Also, the symbol is known as Saint John's Arms or Saint Hannes cross (related to Swedish "sankthanskors", Danish "johanneskors", and Finnish "hannunvaakuna"), as Gorgon loop, and as command key symbol due to its use on the command key on Apple computer keyboards.