[jquery]
- learn here
  -> http://learn.jquery.com/

-  $(function() {} is same as $(document).ready(function() {},
   $(window).load(function () {} comes later in rendering process when all
   tags are ready such as images
   -> DOM way, in case jQuery hasn't loaded yet and is undefined, e.g. jQuery gets loaded in footer
    - https://developer.mozilla.org/en-US/docs/Web/Events/DOMContentLoaded

- stop the default action
  e.g. you have an anchor and register a listener for a .click() event using
  jquery, but you don't want default href="foo" behavior so you do:
  
  event.preventDefault(); /* prevent href from doing its job */
  return false;           /* stops bubbling up */

- the $() is a constructor call, $ is a variable name, js doesn't prepend var names with $
  -> find() is similar, and can be chained

- very common jquery uses
  -> you make a selection using $('your search') and you wonder what you got back
     - you loop with .each(function {});
     - use .length, http://learn.jquery.com/using-jquery-core/faq/how-do-i-test-whether-an-element-exists/
       e.g. if ($('$foo').length) /* heck yeah */ ;

- useful api funtions
  -> trigger(), e.g. you want to click event to happen on some element at your will,
     exmaple: ('div.clips a:first').trigger('click');
  -> after(), append a new element after current, e.g. $('#foo').after('<div id="bar">hell</div>');
  -> is(), e.g i used it to check if arr content of arr at some index is empty, below:
     if (!$(transcripts_divs[ind]).is(':empty')) { /* do something awesome */ }
  -> walking DOM tree
     - parent(), parentUntil()
     - next(), children()