Upside down question and exclamation
¡Hola! Upside down question ¿ and upside exclamation ¡ marks are native to Spanish language. That's why operating system developers of Windows, Mac and Linux made it possible to type upside down characters ¿¡ straight from keyboard. I'll show you how to do it with using different techniques depending on your Operating System and tastes.
Upside down text
˙sloqɯʎs ƃuısn ʎq upside down sʇxǝʇ ǝloɥʍ dılɟ oʇ ǝboqɐ pǝllɐɔ ɹoʇɐɹǝuǝƃ ƃuıʇsǝɹǝʇuı uɐ ǝsn uɐɔ noʎ ʇɐɥʇ ʎɐs oʇ ʇuǝɯoɯ ʇɥƃıɹ ǝɥʇ ɹoɟ ʇıɐʍ ʇ,uplnoϽ
What upside down marks means
Upside down question and exclamation marks are punctuation marks of Spanish language used to begin interrogative and exclamatory sentences. They can also be combined in several ways to express the combination of a question and surprise or disbelief. The initial marks are normally mirrored at the end of the sentence or clause by the common ? and ! marks used in most other languages.
I'll give you several examples of use for clearence.
¡Y tú quién te crees que eres? ("Who do you think you are?!")
¿¡Y tú quién te crees que eres!?, ¡¿Y tú quién te crees que eres?!
¿Por qué dices eso? ("Why do you say that?")
More information on usage and stuff can be found on Inverted question mark and exclamation point article on Wikipedia. I'll proceed with the ways you can type upside down characters from keyboard.
How to type upside down characters?
Choose your system and find out.Windows
Shortcut technique that works on Desktops and most Laptops running MS Windows. You press Alt and, while holding it, type a code on Num Pad while it's turned on. Please, read a guide if you're running a laptop. You can type many frequently used symbols with this method.
Configure your keyboard layout in Windows so that you can type all additional symbols you want as easy as any other text. Takes about 5-10 minutes to set things up, but you'll be typing like a boss. You can assign upside down symbols and any other text characters to your keyboard using this technique.
CharMap allows you to view and use all characters and symbols available in all fonts (some examples of fonts are "Arial", "Times New Roman", "Webdings") installed on your computer. You can input upside down symbols using it.
Emoji on iOS (iPhone, iPad and iPod touch)
You can make frequently used technical non-fancy symbols like "√ ∑ π ∞ ∆ ™ © æ £ ¢" and åccénted letters on Mac using [Option] key. I've compiled a list of shortcuts in my article and explained how to open keyboard viewer. You can also use your Keyboard Viewer as an alternative to my list.
[Option] +  produces ¡ upside down exclamation sign and [Option] + [/] + [Shift] produces ¿ upside down question sign.
Character Palette allows you to view and use all characters and symbols, including upside down signs, available in all fonts (some examples of fonts are "Arial", "Times New Roman", "Webdings") installed on your computer.
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There actually are 3 different ways to type symbols on Linux with a keyboard. And all of them can produce upside down text symbols.
Character map allows you to view and use all characters and symbols available in all fonts (some examples of fonts are "Arial", "Times New Roman", "Webdings") installed on your computer. It can also help you lookup Unicode codes for entering symbols with keyboard.
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