An oral history of the hashtag:
Whether you first knew # as a number sign, the pound symbol, or a tic-tac-toe board, its incarnation as the hashtag has changed language for millions around the world. Sure, it can indicate where you’re posting from (#OvalOffice) or what you’re posting about (#FakeNews). But it has also shaped elections, launched social movements, and transcended its meaning as a mere keystroke to become a defining symbol of the digital age. Its story started on a bare-bones social-networking site called Twitter back in 2007, when early adopters began developing tools to organize their tweets.
Read the rest at Wired.