Caspases are essential enzymes in apoptotic cell death, functioning as a family of cysteine proteases. They play a critical role in the cleavage of specific cellular proteins, which is essential for the morphological and cellular events during apoptosis. Caspases are divided into subfamilies based on their structural and functional characteristics, with group I caspases involved in cytokine processing, group II caspases as major effectors of cell death, and group III caspases as upstream activators. The structure of caspases includes a catalytic domain and a prodomain, with the active site containing a conserved cysteine and histidine residue. Caspases recognize a specific tetrapeptide sequence in their substrates, with variations in substrate specificity among different caspase subfamilies. Caspase activation can occur through recruitment, trans-activation, or autoactivation, with the latter involving proteolytic cleavage of the enzyme itself. Caspases are involved in the cleavage of numerous proteins during apoptosis, including PARP, DNA-PKcs, Rad51, DFF45/ICAD, and others. Aberrant caspase activity can contribute to disease pathogenesis, as seen in polyglutamine-repeat disorders and Alzheimer's disease. Caspase inhibitors are being explored as potential therapeutic agents for diseases involving inappropriate apoptosis, such as cancer and neurodegenerative disorders. Current research focuses on developing selective caspase inhibitors and understanding the molecular mechanisms underlying caspase function and regulation.Caspases are essential enzymes in apoptotic cell death, functioning as a family of cysteine proteases. They play a critical role in the cleavage of specific cellular proteins, which is essential for the morphological and cellular events during apoptosis. Caspases are divided into subfamilies based on their structural and functional characteristics, with group I caspases involved in cytokine processing, group II caspases as major effectors of cell death, and group III caspases as upstream activators. The structure of caspases includes a catalytic domain and a prodomain, with the active site containing a conserved cysteine and histidine residue. Caspases recognize a specific tetrapeptide sequence in their substrates, with variations in substrate specificity among different caspase subfamilies. Caspase activation can occur through recruitment, trans-activation, or autoactivation, with the latter involving proteolytic cleavage of the enzyme itself. Caspases are involved in the cleavage of numerous proteins during apoptosis, including PARP, DNA-PKcs, Rad51, DFF45/ICAD, and others. Aberrant caspase activity can contribute to disease pathogenesis, as seen in polyglutamine-repeat disorders and Alzheimer's disease. Caspase inhibitors are being explored as potential therapeutic agents for diseases involving inappropriate apoptosis, such as cancer and neurodegenerative disorders. Current research focuses on developing selective caspase inhibitors and understanding the molecular mechanisms underlying caspase function and regulation.