Ceph can provide storage as block, object or file FileSystem
Block
A Ceph block device can be created with 2 commands:
ceph osd pool create POOL_NAME
rbd pool init POOL_NAME
Block devices can be integrated with various tools such as Openstack and Kubernetes to provide backend block storage to VMs or PV storage via the Ceph CSI respectively.
File System
Ceph storage can also be overlayed with a filesystem using CephFS which can then be mounted.