RAID

A Redundant Array of Independent Disks combines multiple physical drives behind one logical storage volume. Different levels trade capacity, speed, and fault tolerance: RAID 1 mirrors data, while RAID 0 stripes it for performance with no redundancy. Windows users usually encounter the array through motherboard firmware, a dedicated controller, or Storage Spaces. Setup may require a controller package before the volume appears. Do not switch an existing Windows installation between AHCI and RAID modes casually; the active storage stack may no longer start. A redundant array also is not a backup, because deletion, corruption, malware, and controller failure can affect the entire volume. Keep a separate copy of important files before rebuilding or replacing any member disk.