If there was ever a controller that was obviously based on the design of the Super Nintendo controller, this is it. Sony didn't even try to hide the fact - I'm pretty sure their motivation went something like this: "We are going to beat you at your own game, and we're going to rub it in your face while we do it!"
The story is that the original
Playstation was to be Sony/Nintendo partnership in the form of a CD add-on for the Super Nintendo. At some point Nintendo suddenly terminated the project, infuriating Sony. Sony vowed to take revenge and developed their own game console.
The only significant alterations to the design are the addition of two additional
, and handles to make the controller more comfortable to hold. Because games would now be in 3D, the additional shoulder buttons were originally intended for the purpose of allowing players to move in or out along that extra 3rd dimension.