Logical volume management
In computer storage, logical volume management (LVM) provides a method of allocating space on mass-storage devices that is more flexible than conventional partitioning schemes to store volumes. In particular, a volume manager can concatenate, stripe together or otherwise combine partitions (or block devices in general) into larger virtual partitions that administrators can re-size or move, potentially without interrupting system use.
Source: Wikipedia — Logical volume management (CC BY-SA 4.0)