How to distinguish RAID from LVM and what are their main differences?

RAID (Redundant Array of Independent Disks) and LVM (Logical Volume Manager) are different disk management technologies:

• RAID combines multiple physical disks into a single logical array to improve performance, fault tolerance, or both. For example, RAID 0 for speed, RAID 1 for mirroring.
• LVM operates on top of physical or RAID disks and allows creating logical volumes that can be dynamically resized, snapshotted, and grouped.

Main differences:

• RAID is a hardware or software level for organizing disks into arrays with redundancy.
• LVM is a software level for flexible partition and volume management.

Example: you can create a RAID array for reliability, and then set up LVM on top for easy management of partitions.