Workloads are objects you use to manage and run your containers on the cluster.
Discovery & LB resources are objects you use to "stitch" your workloads together into an externally accessible, load-balanced Service.
Config & Storage resources are objects you use to inject initialization data into your applications, and to persist data that is external to your container.
Cluster resources objects define how the cluster itself is configured; these are typically used only by cluster operators.
Metadata resources are objects you use to configure the behavior of other resources within the cluster, such as HorizontalPodAutoscaler for scaling workloads.