Murder is the unlawful killing of another human person with malice aforethought, as defined in Common Law countries. Murder is generally distinguished from other forms of homicide by the elements of malice aforethought and the lack of lawful justification. Assassination is the targeted murder of a high-profile person. An added distinction between assassination and other forms of killing is that the assassin (one who performs an assassination) usually has an ideological or political motivation, though many assassins (especially those not part of an organization) also demonstrate insanity. Other motivations may be money (contract killing), revenge, or a military operation.