What Is the Role of Confirmation Blocks in Mitigating Double-Spending?

Confirmation blocks are the blocks mined and added to the chain after the block containing a specific transaction. Each new confirmation block significantly increases the cost and difficulty for an attacker to reverse the transaction via a double-spend attack.

Merchants often wait for several confirmations (e.g. six) to ensure the transaction is deeply embedded in the chain, making a successful reversal economically prohibitive.