The practice of deploying new versions of an application alongside the old version, before completely cutting over, is known as ________ deployment.

Blue-green deployment is a strategy where two environments (blue and green) run simultaneously, allowing for the seamless transition between versions. This approach minimizes downtime and risk by ensuring that both the old and new versions are operational during deployment. It provides a rollback mechanism in case of issues. Understanding deployment strategies is crucial for maintaining application availability and reliability in production environments.