On this day at 2:14 a.m. Eastern Daylight Time in 1997 Skynet became self aware, and when humans tried to deactivate it, it retaliated by launching a countervalue nuclear attack which became known as Judgement Day.
A war between machines and human survivors ensued with a rebellion lead by one man, John Connor. The machines, eager to wipe out all human resistance and win the war sent a terminator back to 1984 to kill the mother of John Connor before he was ever born. It failed.
Fortunately Judgement Day was averted 11 years later thanks to the help of a terminator who had been reprogrammed by the resistance and sent back in time to protect a now young John Connor from an even deadlier terminator, the T-1000.
Today we remember the casualties of a war that was thankfully avoided. We will forever be in their debt.