What is the relationship between CI and CD in a Docker-based workflow?

CI (Continuous Integration) covers building and validating the image — compiling, testing, scanning, and pushing a trustworthy artifact to a registry. CD (Continuous Deployment/Delivery) covers getting that validated image running in target environments — whether via direct deploy scripts, Kubernetes rollouts, or a GitOps controller reconciling a manifest repository. Docker's immutable, registry-distributed image format is what makes a clean handoff between these two phases possible.