Single Docker engine:

- you use 'docker' command to talk to Docker engine.
- Docker engine pull images from repo, like OCIR
- Image is run inside container
- Container can have persistent volume 
  ex, local directory/file or NFS share
- Container's service can be accesses via host/container port mapping

K8s

- you use kubectl command to talk to master API server
- kubelet on worker nodes talk to API server
- then kubelet manages Docker engine on worker nodes
- from here is almost same as on single Docker engine
- Docker engine pull images from repo, like OCIR
- Image is run inside container, and container inside Pod
  so Pod is single unit of deployment in k8s
- Pod can have one or more container, and persistent volumes
- Final component is service, ex. LoadBalancer for accessing app from outside k8s cluster