Function Call

Function Call

  2. function show() {
  3.     var offset = $("#child").offset();
  4.     var posY = offset.top - $(window).scrollTop();
  5.     var posX = offset.left - $(window).scrollLeft();
  6.     
  7.          $("#output").html("top:" + posY + ", left:" + posX);
  8.    
  9. }

  11. show();
  12. $(window).scroll(show);


Well I understand that 
  2. $(window).scroll(show);

means that execute the code when the window starts scrolling , but than why is that thing 

  1. show();
In the code , i don't get its relevance , what is it really doing ?