Cells exist in dynamic environment that requires virtually continuous control mechanisms with expenditure of energy to maintain homeostasis. Cell death may be physiological or histopathological. Apoptosis is an active ,energy dependent process that occurs as part of normal tissue or organ functioning. Apoptosis is pathway for rapid and efficient killing of unnecessary or damaged cells which is required for sculpting tissues in normal development and is a part of the host defence mechanism against disease. Between 50 billion and 70 billion cells die each day due to apoptosis in the average human adult!!