Pods, ReplicaSets, and Deployments

Every container you run on Kubernetes lives inside a Pod. But you almost never create a Pod directly. Three resources work together to get your container running and keep it running: Pods, ReplicaSets, and Deployments. Each one solves a problem the one below it can't.

This matters for the KCNA exam because Kubernetes Fundamentals accounts for 44% of the questions. The exam tests conceptual understanding: not whether you can write a Deployment manifest from memory, but whether you understand what happens when you change a container image in a Deployment spec, or why a bare Pod won't recover after a node failure.