Transitional justice originally referred to how to deal with past human rights violations in countries which were experiencing transitions from non-democratic to democratic systems. After the Cold War and the upheaval in East Europe, this concept was further used to refer to how to cope with past atrocities in the aftermath of wars or conflicts. In recent years, some developed countries' governments take many reparation programs such as apologies and compensations to comfort the groups which were historically discriminated and repressed by dominating groups. These activities are also called transitional justice. The United Nations and the international community have devised various mechanisms of transitional justice, including prosecutions, reparations, truth-seeking, institutional reforms, vetting and so on. In a word, transitional justice is a response to systematic or widespread violations of human rights. Transitional justice might not be understood as an ontological and special idea of justice, but a methodology to reconcile ideal justice and real politics. Moreover, what transitional justice emphasizes is neither an absolute justice idea nor a coherent justice model.