Since the dawn of the digital computer, sci-fi authors have dreamed of a world that exists solely inside a machine. As technology progressed, it became possible not only to re-create our analogue world in computer software, but to include many people, far flung but connected through a network, in that shared experience. These are online worlds, worlds in which representations of distant human players inhabit virtual space together, whether in 3D, 2D or text form.
Here’s a look at 11 of the most influential online virtual worlds ever created, ordered from least influential to most. These worlds aren't necessarily the first, or the best of their kind, but they've had the most influence on the online worlds that followed.