© Wikimedia Commons, GNU Free Documentation License 1.2. Author: Lars Karlsson (Keqs), 5 January 2007.
When you take a new Rubik's Cube out of the box, it is in a highly ordered state. However, it doesn't take long before it is in a highly disordered state, with colored squares seemingly randomly distributed. It is very easy to go from one apparently random state to another, but not so easy to find the path through all the possible states that leads back to the original configuration. This is a hierarchical distribution of states not unlike the states available to an unraveled protein molecule trying to fold into its optimal shape. (Unit: 9)