Core Concepts & Cluster Architecture
Cluster: The whole Kubernetes system.
Node: A machine (VM or physical) in the cluster.
Master/Control Plane: Manages the cluster (API Server, Scheduler, Controller Manager, etcd).
Worker Node: Runs application workloads.
etcd: Key-value store for cluster data.
Kubelet: Node agent that manages pods.
kubectl: Command-line tool for interacting with the cluster.
Namespace: Logical partitioning of cluster resources.