I am surprised that nobody has yet asked this, but what exactly is deployment.apps?
I see it often in commands e.g
kubectl rollout pause deployment.apps/nginx-deploymentor even used interchangably for the deployments keyword:
kubectl get deployments= kubectl get deployment.apps
I do not understand what it indicates though. Even in K8s official docs, they just take for granted that the reader understands the term.
Could someone please explain it to me?
Kubernetes API has its different resources (e.g. Pods, Deployments, Ingress) grouped in what they call "api groups" and in the notation deployment.apps - "deployment" is the resource name and the "apps" is the api group name.
Also see the motivation for API groups