What is the difference between a Blue/Green deployment and a Canary deployment?

Blue/Green: You maintain two identical environments. “Blue” is live, “Green” has the new version. You switch all traffic from Blue to Green at once. Rollback is instant — just switch back. Downside: doubles infrastructure cost.

Canary: You gradually shift traffic from the old version to the new one — e.g., 5% → 25% → 50% → 100%. You analyze metrics and errors at each stage. Slower but safer for catching issues that only appear under real production load.