A RAID Controller is a hardware or software component that manages the Redundant Array of Independent Disks (RAID) configuration in a computer system. Its primary function is to combine multiple hard drives into a single unit, improving data redundancy and performance. By distributing data across several disks, it helps protect against data loss in case one drive fails. RAID Controllers can be found in servers and high-performance workstations, where data integrity and speed are crucial. They come in two types: hardware RAID controllers, which have their own processor and memory, and software RAID controllers, which rely on the system's CPU for management tasks.