13 years ago today DOOM is released. widely recognized for its
pioneering use of 3D graphics, networked multiplayer and custom
expansions creations, DOOM is one of the landmark games that
popularise the First Person Shooter genre.
Distributed as shareware, Doom was downloaded by an estimated 10
million people within two years. As a sign of its impact on the
industry, games from the mid-1990s boom of first-person shooters
are often known simply as "Doom clones".
summarised
from wikipedia