understanding $ vs. jQuery in iife instead of $ -

I'm trying to understand that there is a difference:

  (function ( $) {...}) (jQuery);   
 versus  
  (function ($) {...}) ($);   
 Note that jQuery was replaced with $ This is OK? Is it not used anywhere because it can not work? It works but maybe it is non-standard? Can anyone explain that this is an error or if it is okay? Thanksgiving   
 
 
 Other javascript frameworks can also use $ as a shortcut. The guarantee is that $ is $ inside your function, finally defining jQuery and not the $ pass function or "code area" to ensure that this type is actually $ jQuery when mixing a framework.