The PowerBook 100 was the first PowerBook to incorporate SCSI Disk Mode, which allowed it to be used as an external hard disk on a desktop Macintosh. This provided a convenient method for software to be installed onto the PowerBook or transferred to the desktop, without the need for the 100's optional floppy disk drive. A specialized SCSI cable with a unique connector was required, however, to use any SCSI device on the PowerBook series. A second dedicated cable was required for SCSI Disk Mode. This feature was unique to the 100 until Apple introduced new PowerBooks more than a year later.