In blockchain networks, a block is created containing a set of transactions. Once the block is published, nodes in the network perform the process of confirming the validity of the transactions according to the consensus algorithm of the network (such as Proof of Work or Proof of Stake). Once a block is confirmed, it is added to the chain, making the transactions irreversible and secure. The number of subsequent blocks added to the chain after a block is referred to as its confirmation count, which also indicates how secure the transactions in that block are. Higher confirmation counts can generally indicate a lower risk of reversal.