Crime
The literal meaning of the word crime refers to an act that is unlawful; however there can be interpretations of the word "unlawful" depending on whether the act is looked at through a legal, societal, or moral viewpoint.
Legal crimes are those which explicitly have written laws against--theft for example. However there are such charges that can be brought against an individual titled "Crimes against humanity" which also have laws that stipulate the extent to which that phrase may be used.
From a moral standpoint, a crime can be considered anything that extravagantly violates someone's personal, or spirital beliefs; such victims of those crimes may feel that they have been "wronged", when in fact no legal precedent may exist. In some cases these crimes fall into legal gray areas that cannot be explicitly defined, because of the long lasting impact it may have on societal rules and values.
War crimes are those which charges are brought up against one who commits heinous acts during a time of conflict. Many of the Nazi elite were brought up on war crimes during the Nuremburg trials; a few committed suicide in order to escape their fates.