New to programming and trying to understand it all.

[eluser]xwero[/eluser]
The function is a constructor which means it gets executed when the class is called.

The parent::Controller() line is to inherit the constructor of the Controller class. This is needed if you want to add things to the constructor of your extended class otherwise you overwrite the Controller class constructor and you are going to end up with errors.

It is explained in the user guide but it isn't that clear.