4 Answers

The word "karma"  simply means or refers to the natural law of "Cause and Effect.  Simply put for the literal world, street wise, "what goes around comes around, what one puts out one gets back sooner or later."  It is expressed in many sayings.  For instance:  ":Judge not lest ye yourself be judged." an eye for and eye and a tooth for a tooth." 

These are but metaphors warning one of the impact of one thoughts and deeds; for good or for evil upon themselves.  And indeed, it is true all men in this world suffer, even good men; although good men do not suffer the viciousness of this realm.

For though we may not get all we desire in this world, but what we do get out of this Existence, we have planted our own seeds, by our beliefs, thoughts and action.  If good then happiness, if evil the dues of our own choices.  No blame on the world or on anyone else.

We are all subject to Natural Law whether we believe it or not, and by its aspect of Karma are our lives are a testament to it.  For by it we alone are our own judges.  God Bless. be Good be happy.  :-)

I think good Karma - bad Karma is something that one makes for oneself in this life and believed to decide one's fate in the next.  It comes from Buddhism and Hinduism.