kubelet

Running on every node in the cluster, kubelet is a service that's responsible for ensuring that container workloads (Pods) that have been assigned by the control plane are executed. Additionally, it is also responsible for the following:

• Reporting node and Pods statuses to the API Server
• Reporting resource utilization
• Performing the node registration process (when joining a new node to the cluster)
• Executing liveness and readiness Probes (health checks) and reporting their status to the API Server

To perform actual container-related operations, kubelet uses a container runtime.