Unix Operating System

• Administration
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• Computers: Software: Operating Systems: Network: Distributed: Plan 9 

• Unix Realm  - Provides information on UNIX related topics for system developers. Includes downloads and links.
• UnixGeeks.org  - Provides free UNIX resources to users. Contains brief overview, tutorials, tools and FAQs.
• Windows vs UNIX  - Discusses about the comparison of Windows and UNIX operating systems. Includes resources and forums.