Kubernetes labels are key-value string pairs that link identifying metadata to Kubernetes objects. They provide teams with integrated support for using labels to retrieve and filter the data from the Kubernetes API and carry out bulk operations on selected objects. Labels can be used to group resources, perform bulk operations, schedule pods based on node labels, and aid in cost monitoring. To effectively use Kubernetes labels, it is recommended to follow best practices such as standardizing label naming conventions, avoiding unnecessary changes to labels, using label-selection options, not storing application-level semantics or sensitive information in labels, adding labels to pod templates, automating the labeling practice, and utilizing labels for cost monitoring. By implementing these best practices, teams can realize tremendous benefits from infrastructure visibility and efficient operations.