 
  
 javascript element(s)
-  function(s) -- function name( args ) { ... } 
-  event(s) -- onload, mouse, key, timer 
-  variable(s) -- var x = expression;
-  constructor(s) -- function object() { attribute: value; }
-  closure(s) -- x = function () { ... }
-  meta-programming -- x = eval(string)
