A process by which a transaction is verified and added to the blockchain. Each confirmation represents the addition of a new block to the chain after the block containing the transaction. The more confirmations a transaction has, the more secure and irreversible it becomes. For example, if a transaction is said to have three confirmations, it means that three blocks have been added to the blockchain since the block containing that transaction. Multiple confirmations are typically required to ensure the reliability and integrity of the transaction, reducing the risk of double-spending or fraud.