title: Are global variables just properties on the `window` object?
body: <p>Whenever I see a website on the browser an instance of javascript is running. And I can declare a global variable in the console (DevTools); </p>
  
  <pre><code>var a = 1234567890; 
  </code></pre>
  
  <p>This variable has been declared in global scope such that I can get the value of the variable like so; </p>
  
  <pre><code>&gt; a 
  1234567890
  </code></pre>
  
  <p>However, I can also do this; </p>
  
  <pre><code>&gt; window.a 
  1234567890 
  </code></pre>
  
  <p>Am I understanding it correctly that the <code>window</code> object is the object that contains all the global variables within the website instance on the browser? If so to what scope does the window object belong? This is confusing me a little bit; </p>
  
  <pre><code>&gt; window 
  Window {top: Window, window: Window, location: Location, external:, ...}  
  &gt; window.window 
  Window {top: Window, window: Window, location: Location, external:, ...}  
  &gt; window.window.window 
  Window {top: Window, window: Window, location: Location, external:, ...}  
  </code></pre>
  
  <p>Is the <code>window</code> object the ultimate global object and does that have an object called <code>window</code> that refers back to itself? </p>