It's national punctuation day! In his new book Shady Characters, Keith Houston investigates the origin and evolution of such punctuation marks as the asterisk (*), the dagger (†), the at sign (@), the pilcrow (¶), and the octothorpe (#). But it is the quest of a father and son to invent a symbol for sarcasm that will live in infamy.
Keith Houston, the author of Shady Characters: The Secret Life of Punctuation, Symbols, and Other Typographical Marks, blogs about unusual marks of punctuation at Shady Characters. He lives in Scotland.