Caspases are a family of cysteine proteases that play a central role in the execution phase of apoptosis. They are synthesized as inactive proenzymes and are activated through cleavage in response to apoptotic signals. Initiator caspases such as caspase-8 and caspase-9 activate downstream effector caspases like caspase-3, -6, and -7, which then cleave various cellular substrates leading to the disassembly of the cell.