Which drive standard is less common today and required master/slave configuration for multiple drives?

The drive standard that is less common today and required a master/slave configuration for multiple drives is IDE (Integrated Drive Electronics), also known as PATA (Parallel ATA). This configuration allows two devices to be connected to a single IDE channel on the motherboard, where one device would be set as the master and the other as the slave. This designation determined which device would take precedence when the system attempted to access the drives.

IDE drives were widely used in older computer systems prior to the rise of SATA (Serial ATA). While SATA has become the standard for newer drives, allowing for faster data transfer rates and simpler cabling without the need for master/slave configurations, IDE has largely fallen out of favor. USB and NVMe are also not applicable here, as they function under different standards and technologies, focusing on external connections and high-speed storage, respectively. IDE's dependency on the master/slave setup is a significant distinguishing characteristic that reflects its age and the evolution of drive technology.