NetApp is really vague about terminology translation, but a traditional RAID is called a volume group, and a distributed RAID is called a disk pool.

IBM calls both “managed disks”, and just referrs to them as RAID/TRAID vs DRAID.

The group of these is called an aggregate in OnTap, or a managed disk group in Spectrum Virtualize.

The next layer is a volume in NetApp, or a child pool (optional) in IBM.

NetApp then lets you share a volume via NFS or CIFS, or create a LUN which is really just a well aligned file in a volume. IBM calls them virtual disks, but does not offer NFS/internally.

IBM offers SONAS (Scale Out NAS) which can take LUNs from SVC and share them out. SONAS was called V7000 Unified at one point, but now the storage is unbundled. It uses General Parallel File System (GPFS aka Multi Media File System), Cluster System Manager, and a few other tried and true technologies under the covers giving a lot of options for expansion, but also a cost.