Apple HD20 is an external hard drive.

This device provided 20 megabytes of external data storage. Although developed by Apple specifically for use with the Macintosh 512k, this HD20 was used by the donor with his 128k Macintosh, for which additional memory was required. Connection was made via a floppy disk port, and it ran at the same speed as a floppy disk - slowly. It could store the equivalent of 50 400k floppy disks . It could be daisy-chained to a further Apple HD20 or external floppy disk drive.

The HD20 was rendered redundant by the introduction of the SCSI (pronounced 'scuzzy') interface on the Macintosh Plus in 1986, which supported faster data transfer.

This item is part of a representative collection of hardware, software, trade literature and promotional material that documents the history of the Apple company, and its contribution to, and impact on the computer industry and society.

Physical Description

Rectangular beige plastic box with small coloured Apple company logo at front and vents along the sides and at the rear.

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