Explain the concept of "two-phase commit" in the context of distributed transactions.

The "two-phase commit" protocol ensures atomicity and consistency in distributed transactions. In the first phase, a coordinator node sends a prepare message to all participating nodes, asking if they are ready to commit. If all nodes respond affirmatively, in the second phase, the coordinator sends a commit message, and all nodes execute the transaction. If any node fails to respond or votes against committing, the coordinator sends an abort message, and all nodes roll back the transaction, ensuring consistency across the distributed system.