Clarification on v1 API groups

Hello,

I'm reading the "v1 API Group" page in the "06. API OBJECTS" section. One of the things I read is that "Currently, there are eight v1 groups." I'm confused here as to what those groups are. I see four of them listed on the page, but I don't see how they tie in to this concept of API groups.

I did run the command that gets the API groups on my lab cluster, and this is what I got:

$ curl $APISERVER/apis --header "Authorization: Bearer $TOKEN" --insecure

{
  "kind": "APIGroupList",
  "apiVersion": "v1",
  "groups": [
    {
      "name": "apiregistration.k8s.io",
      "versions": [
        {
          "groupVersion": "apiregistration.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "apiregistration.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "apps",
      "versions": [
        {
          "groupVersion": "apps/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "apps/v1",
        "version": "v1"
      }
    },
    {
      "name": "events.k8s.io",
      "versions": [
        {
          "groupVersion": "events.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "events.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "authentication.k8s.io",
      "versions": [
        {
          "groupVersion": "authentication.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "authentication.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "authorization.k8s.io",
      "versions": [
        {
          "groupVersion": "authorization.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "authorization.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "autoscaling",
      "versions": [
        {
          "groupVersion": "autoscaling/v2",
          "version": "v2"
        },
        {
          "groupVersion": "autoscaling/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "autoscaling/v2",
        "version": "v2"
      }
    },
    {
      "name": "batch",
      "versions": [
        {
          "groupVersion": "batch/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "batch/v1",
        "version": "v1"
      }
    },
    {
      "name": "certificates.k8s.io",
      "versions": [
        {
          "groupVersion": "certificates.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "certificates.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "networking.k8s.io",
      "versions": [
        {
          "groupVersion": "networking.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "networking.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "policy",
      "versions": [
        {
          "groupVersion": "policy/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "policy/v1",
        "version": "v1"
      }
    },
    {
      "name": "rbac.authorization.k8s.io",
      "versions": [
        {
          "groupVersion": "rbac.authorization.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "rbac.authorization.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "storage.k8s.io",
      "versions": [
        {
          "groupVersion": "storage.k8s.io/v1",
          "version": "v1"
        },
        {
          "groupVersion": "storage.k8s.io/v1beta1",
          "version": "v1beta1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "storage.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "admissionregistration.k8s.io",
      "versions": [
        {
          "groupVersion": "admissionregistration.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "admissionregistration.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "apiextensions.k8s.io",
      "versions": [
        {
          "groupVersion": "apiextensions.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "apiextensions.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "scheduling.k8s.io",
      "versions": [
        {
          "groupVersion": "scheduling.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "scheduling.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "coordination.k8s.io",
      "versions": [
        {
          "groupVersion": "coordination.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "coordination.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "node.k8s.io",
      "versions": [
        {
          "groupVersion": "node.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "node.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "discovery.k8s.io",
      "versions": [
        {
          "groupVersion": "discovery.k8s.io/v1",
          "version": "v1"
        }
      ],
      "preferredVersion": {
        "groupVersion": "discovery.k8s.io/v1",
        "version": "v1"
      }
    },
    {
      "name": "flowcontrol.apiserver.k8s.io",
      "versions": [
        {
          "groupVersion": "flowcontrol.apiserver.k8s.io/v1beta3",
          "version": "v1beta3"
        },
        {
          "groupVersion": "flowcontrol.apiserver.k8s.io/v1beta2",
          "version": "v1beta2"
        }
      ],
      "preferredVersion": {
        "groupVersion": "flowcontrol.apiserver.k8s.io/v1beta3",
        "version": "v1beta3"
      }
    }
  ]
}

As you can see, I'm getting way more than eight groups back. Should I take this to mean that the "eight v1 groups" mentioned in the lesson are out of date? I want to make sure that I understand the concepts fully.

Thank you!