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Freebyte's Guide to Operating Systems, Free and Non-free - http://freebyte.com/operatingsystems/
Includes: open source, commercial; Unix (BSDs, Linux); Amiga; BeOS, Zeta; RiscOS; DOS, Windows-emulators; educational; a few related topics. |
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The OS Files - http://www.theosfiles.com/
Portal for many x86 PC platform operating systems; details, news, information, secret tips, background, links, availability (current, planned); DOSs, Linux, NetWare, OS/2, Unix, Windows. |
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Information about Operating Systems - http://www.operating-system.org/
Operating System Documentation Project, OSDP: information on many OSs and their developers; independent objective descriptions, facts, history; in text and screenshots. [English, German, French] |
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Vintage OS - http://www.vintageos.org/
Information, consulting on DOS, Windows, OS/2, Unix, BSD, Mac, MVS, Palm OS, UNIX, and other vintage operating systems. |