Before the uproar begins, there is no competitor for real computing.
Once you go SCSI, nothing else is quite the same...
ST412 / ST506 Drive Interface
The drive controller sits on a card. There is no drive
controller on a device.
IDE Drive Interface
The slot may take the guise of an embedded port or a paddleboard
plugged into a system slot. The IDE/EIDE disk controller is embedded in
each device. Each drive sits on the bus. Newer ATA drives employ bus mastering.
Better late than never...
SCSI Device Controller Interface
The blessings of SCSI: reliable support of external devices,
different devices, more devices (ranges from 7 to 15 devices). SCSI may
appear as a built-in port, however it still provides a separate signal
bus to attached devices.