Simple definition
A Kubernetes StorageClass defines a storage class and provisioner used to create persistent volumes on demand.
Purpose and use
A Kubernetes StorageClass describes a storage category and parameters for provisioning compatible volumes.
How does it work?
The provisioner and its options apply when a persistent volume claim selects the class; rules can also govern binding, expansion and reclamation.
Example and verification
Before storing important data, verify reclaim policy and behavior after a volume claim is deleted.
Points to watch
A class alone guarantees neither replication, backup nor performance. A deletion policy can remove associated storage according to provisioner behavior.
In short
A StorageClass is a provisioning contract to validate against actual storage and data lifecycle.