The Past and Future of Punctuation Marks

It's hard to imagine reading without punctuation marks, but that was the situation until the early Middle Ages. Modern punctuation didn't get standardized until the invention of the printing press.

All this is laid out in a rather fascinating article, Pause and Effect.

The printing press allowed the standardisation and rapid spread not only of language and its looks, but also of marks of punctuation. Enthusiastically taken up by humanists and authors across Europe, the correct use of punctuation marks became an intrinsic part of good education and breeding. Yet their ambivalent nature, halfway between speech and writing, continues to reverberate: the 16th-century English educator Richard Mulcaster called brackets, for instance, ‘creatures to the pen, and distinctions to pronounce by’. Their indeterminacy, perhaps, makes theorists of rhetoric and grammar nervous: they prescribed the use of certain punctuation marks as both elegant and reprehensible, something to do by all means – and not do under any circumstances.

The article goes on to discuss the role of puntuation in modern communication, more specifically texting and internet messaging.