&gt; <i>My mind was absolutely blown when I first realized that the function of a CPU is pretty much to read tokens from a stream and perform an action for each.</i><p>My &quot;aha!&quot; moment when I first learned about CPUs was the program counter, or if you&#x27;re an Intel guy, you&#x27;d call it the instruction pointer.<p>The PC might seem obvious, but if you think about it for a moment, you&#x27;ll realize that someone had to have invented it. It&#x27;s not <i>totally</i> obvious. And as far as I can tell, the inventor is unknown.<p>Note also that the featured program does not have a PC, so there are things it can&#x27;t do that a normal CPU can do.