The text discusses the RAID levels 4 to 6, which use an independent access technique. In an array with independent access, each disk member operates independently, allowing for simultaneous read and write operations. This makes arrays with independent access more suitable for applications that require high I/O performance, but less suitable for applications that require high data transfer rates.The text explains how striping is used in RAID levels 4 to 6, where strips are relatively large. In RAID 4, a bit-by-bit parity calculation is performed on the corresponding strips in each data disk, and the parity bits are stored in the parity disk. The text highlights that when a write operation is performed, the software array management needs to update not only the user's data but also the corresponding parity bits. This means that each write operation involves two reads and two writes.