Origins of common symbols

Neatorama posted the origins of several common symbols, reprinted from a book titled Uncle John's Supremely Satisfying Bathroom Reader.

 Images 2007-07 Exclamation-Point
Exclamation Point Origin: Like the question mark, the exclamation point was invented by stacking letters. The mark comes from the Latin word io, meaning "exclamation of joy." Written vertically, with the i above the o, it forms the exclamation point we use today.

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