In the role playing game
Shadowrun, the
Matrix is the
Internet of the mid-late
21st century. Although this information network could be accessed with something that would be recognizable to today's
ubergeek as a
computer, most anything worth doing in Shadowrun's Matrix is done through a direct neural interface, buffered through a bulky keyboard-like apparatus known as a
Cyberdeck.
A "Decker" (Shadowrun's equivalent of our "Hacker") breaks into parts of the Matrix that he is not authorized to view, with huge risks involved. Activity in the Matrix such as "attacking" an intrusion countermeasure program (ICE) or breaking into a locked database occurs in a highly conceptual metaphor for the activities taking place. A "combat" program may appear as a blade or a firearm, for example, while a firewall may actually look like a wall of fire!
Mistakes in the Matrix can be fatal, since the Intrusion Countermeasures can subject the intruder to lethal neurofeedback. Damage to hardware is also a risk.
Besides Deckers, Shadowrun's rules mention an oft overlooked character class called Otaku (which is also a word for a "geek" or someone who is obsessed with anime or anything else). In Shadowrun, an Otaku can use the Matrix by plugging an information lead directly into their Datajack (brain interface implant) without buffering the connection through a Cyberdeck. Otaku can code the necessary algorithms for cyber-combat in their heads, on the fly, and therefore don't need to use a Cyberdeck. The downside of this, of course, is that any damage done to them is much more dangerous, because there is no Cyberdeck to perform damage control or filtering functions.