What’s the difference between ClusterIP, NodePort and LoadBalancer service types in Kubernetes?

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Question 1 – I’m reading the documentation and I’m slightly confused with the wording. It says:

ClusterIP: Exposes the service on a cluster-internal IP. Choosing this value makes the service only reachable from within the cluster. This is the default ServiceType

NodePort: Exposes the service on each Node’s IP at a static port (the NodePort). A ClusterIP service, to which the NodePort service will route, is automatically created. You’ll be able to contact the NodePort service, from outside the cluster, by requesting <NodeIP>:<NodePort>.

LoadBalancer: Exposes the service externally using a cloud provider’s load balancer. NodePort and ClusterIP services, to which the external load balancer will route, are automatically created.

Does the NodePort service type still use the ClusterIP but just at a different port, which is open to external clients? So in this case is <NodeIP>:<NodePort> the same as <ClusterIP>:<NodePort>?

Or is the NodeIP actually the IP found when you run kubectl get nodes and not the virtual IP used for the ClusterIP service type?

Question 2 – Also in the diagram from the link below:

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Is there any particular reason why the Client is inside the Node? I assumed it would need to be inside a Clusterin the case of a ClusterIP service type?

If the same diagram was drawn for NodePort, would it be valid to draw the client completely outside both the Node andCluster or am I completely missing the point?

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