The storage pool is aggregation of storage devices for providing various data services: data protection RAID, compression, deduplication etc.
The basic storage pool is the LVM2 volume group, which provides
Volume Striping (useful only on top of RAID)
Thin provisioning
Dynamic volume resizing
Raid Protection (raid1, raid6) when combined with RaidGroup
Deduplication when combined with KVDO module
Snapshot when used with thinpool
Advanced storage pool with COW
Volume Striping
Unlimited snapshots