Many people will look at the title of this article and think to themselves ‘the AS/400 doesn’t exist anymore’. Others will look at it and think ‘hey, the forward slash between AS and 400 is missing’. All of them will be right of course. But very few of them will realize an ‘AS400’ is not ‘the AS/400’. A simple analogy in plain English covering over 3 decades worth of IBM’s adventures in the world of midrange computer systems can explain why.