RAID (Redundant Array of Independent Disks) is a technology used to improve data redundancy and performance in storage systems. The necessity of RAID depends on specific use cases, such as the need for data protection or increased read/write speeds. For hardware, a RAID controller is essential, and options include dedicated RAID cards or onboard RAID capabilities. A common recommendation is to use a setup with eight drives in a RAID configuration, supplemented by two additional drives on an onboard RAID array. This configuration balances performance and redundancy without requiring excessive speed, which is often unnecessary for traditional hard drives.