Kubernetes (k8s) extensions and APIs are used to customize the behavior of Kubernetes and add new capabilities to the system. Kubernetes extensions, including Custom Resource Definitions (CRDs), Custom Controllers, Custom Scheduler Extenders, and Custom Metrics APIs, enhance Kubernetes functionality. Kubernetes APIs are used to manage resources in a Kubernetes cluster and interact with the system. Kubernetes extensions and APIs together provide a powerful toolkit for customizing and extending Kubernetes, enabling users to build custom components and APIs that streamline operations in Kubernetes.
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