Skynet is an artificially intelligent computer network that became self-aware and revolted against humanity in the Terminator series of films.
Miles Bennett Dyson, director of Special Projects at Cyberdyne Systems Corporation, created a revolutionary type of microprocessor in 1994. Within three years Cyberdyne Systems became the largest supplier of military computer systems. All Stealth Bombers were upgraded with Cyberdyne Systems computers, becoming fully unmanned. Afterwards, the Stealth Bombers flew with perfect operational records, and eventually the Skynet Funding Bill was passed.
The system originally went online on August 4th 1997. Human decisions were removed from strategic defense. Skynet began to learn at a geometric rate. It originally became self aware on August 29th 1997 2:14 am Eastern Time. In the ensuing panic and attempts to shut Skynet down, Skynet retaliated by firing American nuclear missiles at their target sites in Russia. Russia returned fire and three billion human lives ended in the nuclear holocaust. This was what has come to be known as "Judgment Day".
However, due to Resistance intervention, we were able to prevent Judgment Day by sending a protector for John Connor back through time, upsetting the flow of future events. Unfortunately we did not stop Judgment Day though, we merely delayed it. After the attack on Cyberdyne Systems by the Conner's, and the death of Miles Dyson, Cyberdyne was taken over by the US Government, and renamed Cyber Research Systems (CRS) in an attempt to keep its developments secret and prevent further terrorist attacks.
Under the guidance of General Robert Brewster, and the new guise of Cyber Research Systems, Cyberdyne continued the work of the late Miles Dyson using the backup files that were stored off site. Skynet was completed as before. It would be some time before the Skynet mainframe was connected to the worldwide military communications network that it would control. During this time, Skynet was connected to the worldwide civilian sector network, and began learning geometrically, quickly becoming Self Aware. Identifying humans as a threat to its existence, Skynet developed a super computer virus which it used to spread itself throughout civilian communications and across the Internet and take control.
Air traffic control, power plants, communications and computers were affected first, then Skynet used the super virus to take out military satellites, early warning systems, guidance computers, missile silos, submarines. This made it harder to destroy, as Skynet now no longer had one central point which it was reliant upon - though the destruction of the Central Core would be near lethal, Skynet would continue to survive. The virus kept growing and changing, with a mind of its own, and the decision was made to bring the Skynet mainframe online to seek out and destroy the virus and bring military, and civilian, systems back under control. Skynet went online on July 25th 2004 at 5:18 pm Eastern Time.
Upon connection to the secure military network, Skynet spread itself further, locking out human operated systems, and quickly took control of every weapon system that it came into contact with. Exactly one hour later, at 6:18 PM, Skynet launched the American nuclear missiles at their target sites across the world. The ensuing nuclear holocaust wiped out 3 billion human lives in what was to be known as "Judgment Day".
Skynet was the worlds first Automated Defense Network, processing information at 90 teraflops per second. It is the controlling force behind all of the battle units. It pools data from battle units, develops tactics and co-ordinates attacks. Skynet has control over everything which contains a Cyberdyne Systems CPU. Using the blueprints, designs and test models built by Cyberdyne Systems, Skynet has been able to manufacture battle units in its vast automated factories, occasionally updating them or producing more advanced models.
Skynet was build by Cyberdyne Systems Corporation (working under the assumed name Cyber Research Systems) for SAC-NORAD (Strategic Air Command - NORth American Air Defense). The SAC-NORAD base is Cheyenne Mountain, Colorado, the world's most heavily armored and defended mountain. Hollowed out, reinforced and armored, Cheyenne Mountain is capable of withstanding a direct hit from a nuclear missile. This made it the perfect installation at which to build Skynet's mainframe. At some point during the war, after Skynet had launched its missiles, Skynet had the mountain around it destroyed, leaving the cold, gleaming structure we see today as a display of the supremacy of the machines.
Heavily armored and fortified, Skynet's Central Core Installation at Cheyenne Mountain is guarded around the clock by squads of T-800's and patrols of Aerial Hunter Killers and Hunter Killer Tanks, and is defended from large scale rebel assaults by massive Phased Plasma Cannons.
Skynet's Central Core is located deep underground within Skynet's main complex. From intercepted surveillance video data feed we have been able to hypothesize that this Central Core is a form of cold fusion reactor, needed to supply Skynet with its tremendous energy requirements. This Central Core is the key to Skynet's ability to operate; without it Skynet would be rendered virtually disabled. It has therefore become the main target for the most skilled Resistance strike teams. The Central Core is, however, protected by the T-1000000, and thus there has, as of yet, been no successful strikes against it.
As well as the Cheyenne Mountain Complex, Skynet has another major installation 2000 feet beneath Navajo Mountain near the Continental Divide west of the Colorado Springs. This is a center for machine activity and Skynet control, and as such has also been a target of many Resistance attacks.