The epoch – midnight on 1st January 1970 – is one of the most important moments in computing. Many systems store dates and times as the number of seconds (or milliseconds) since the epoch. When new year’s revellers counted down the seconds before Big Ben struck twelve for the first time in a new decade, who would have known that the moment would be significant fifty years on?
Except, it didn’t. On the moment that is represented as zero in Unix, C, Java and so many other systems, Big Ben did not strike twelve. At midnight on the 1st January 1970, Big Ben struck one.