http://72.14.177.54/comp_resource/?action=history&feed=atom&title=Sophisticated_Operating_SystemSophisticated Operating System - Revision history2026-06-14T12:46:07ZRevision history for this page on the wikiMediaWiki 1.15.1http://72.14.177.54/comp_resource/?title=Sophisticated_Operating_System&diff=1457&oldid=prevAdmin at 03:14, 6 April 20082008-04-06T03:14:18Z<p></p>
<p><b>New page</b></p><div>{{Operating system|No Image|1980|1982|Apple III|none|ProDOS}}<br />
The '''Sophisticated Operating System''' (or SOS for short) was for the [[Apple III]]. It influenced the design of [[ProDOS]] and [[Hierarchical File System|HFS]] for the [[Macintosh]].<br />
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== Advantages ==<br />
SOS had many advantages over [[Apple DOS]]. It allowed device drivers for [[hard drives]] and [[RAM disks]], as well as support for [[5 1/4" floppy drive|5 1/4" floppy drives]].<br />
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== Problems ==<br />
SOS was not natively backwards compatible with DOS 3.2 and DOS 3.3, even though the Apple III was backwards compatible with the [[Apple II Plus]] in hardware. Users had to boot an [[Apple II]] emulator disk to run Apple II software.<br />
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The [[IBM PC 5150|IBM PC]], released one year after the Apple III, sealed the Apple III's and SOS's coffin.</div>Admin