Four-and-a-half years ago, Jack Dorsey sent the Tweet that would eventually spark a social revolution. At just 24 characters long, Dorsey and the Twitter team introduced us, one by one, to a new medium for connecting and communicating with one another. It would forever change how its community shared, discovered, and learned, setting the stage for a new era of influence and relevance. And in just four short years, Twitter would emerge as something more personal than a social network,…