What are Zero-Confirmation Transactions?

A zero-confirmation transaction (or "0-conf" for short) is a transaction that has been broadcast to the network but has not yet been included in a block. Because it hasn't been confirmed by being included in a block, there is a risk that the transaction may not be valid and could be reversed. This is because there is a possibility that the same digital assets could be spent multiple times before being confirmed on the blockchain. When a transaction is first…