Editing Apple III (section)

===Peripherals===
The Apple III has four expansion slots, a number that ''inCider'' in 1986 called "miserly".,<ref name="obrien198609">{{cite magazine |last=Obrien |first=Bill |date=September 1986 |title=And II For All |magazine=inCider |url=https://archive.org/stream/inCider_1986-09 |access-date=July 2, 2014| pages=[https://archive.org/stream/inCider_1986-09#page/n37/mode/2up 38], [https://archive.org/stream/inCider_1986-09#page/n91/mode/2up 94–95]}}</ref> also saying Apple II cards are compatible but risk violating government [[electromagnetic interference|RFI]] regulations, and require Apple III-specific [[device driver]]s; ''BYTE'' stated that "Apple provides virtually no information on how to write them". As with software, Apple provided little hardware technical information with the computer<ref name="moore198209" /> but Apple III-specific products became available, such as one that made the computer compatible with the [[Apple IIe]].<ref name="obrien198609" /> Several new Apple-produced peripherals were developed for the Apple III. The original Apple III has a built-in [[real-time clock]], which is recognized by Apple SOS. The clock was later removed from the "revised" model, and was instead made available as an add-on.

Along with the built-in floppy drive, the Apple III can also handle up to three additional external Disk III floppy disk drives. The [[Disk III]] is only officially compatible with the Apple III. The Apple III Plus requires an adaptor from Apple to use the Disk III with its DB-25 disk port.<ref>{{cite web | url=http://support.apple.com/kb/TA31434 | title=Archived - Floppy Disk Drives: Apple III Plus External Drive Adapter | work=Apple | date=February 19, 2012 | access-date=November 23, 2013 | archive-date=December 2, 2013 | archive-url=https://web.archive.org/web/20131202235027/http://support.apple.com/kb/TA31434 | url-status=live }}</ref>

With the introduction of the revised Apple III a year after launch, Apple began offering the [[Apple ProFile|ProFile]] external hard disk system.<ref name = "bott" /> Priced at $3,499 for 5&nbsp;MB of storage, it also required a peripheral slot for its controller card.