DevOps — Blue-Green Deployment

Blue-Green Deployment is a release strategy that minimizes downtime and risk. Two environments are created: one active (blue) and one idle (green). The new version of the application is deployed to the green environment and thoroughly tested. Once everything is confirmed to work correctly, traffic is switched from blue to green instantly. If a problem occurs, you can roll back to the blue environment quickly. This strategy ensures smooth updates with zero downtime.

Example: An e-commerce app updates its checkout system on the green server, then switches user traffic to it once testing is complete.