Updating Labels
At first you created certain group of pod with certain labels and after some time because of business requirement you wanted to change the labels of the pod then instead modifying in the YAML file directly you can do by using the CLI command which is best practice than the editing the source file. To update the labels of the pod use the following command.
kubectl label pods -l Existing-Key: Existing-value New-Key: New-value
Kubernetes – Labels & Selectors
An open-source container management platform called Kubernetes automates the deployment, scaling, descaling, and load balancing of containers (also called a container orchestration tool). It was created by Google in Golang and has a sizable community as a result of that. Google eventually donated it to CNCF (Cloud Native Computing Foundation). In essence, deployment is a layer of abstraction above pods. It resembles a design plan for pods.