In what ways have the two koreas grown apart?

South Korea is a democratic nation while North Korea is a communist nation.  Though both have been separated by boundaries and political ideology, recent developments may have caused the two countries to grow further apart. Today, South Korea is one of the fastest growing countries in the world.  Its economy is now rapidly growing as its products are now widely used internationally from cellphones to appliance to even automobiles.  This has led to big improvement in the living conditions of its citizens who also enjoy the benefits of a democratic government.  On the hand, North Korea is gaining notoriety for its suppression of human rights.  There are rumors of starvation within the country and it recently announced that it successfully detonated a hydrogen bomb heightening tensions not only with the South but also with other countries.