Overview of Unix

Developed in AT&T Bell Labs by Ken Thomson as a single user OS in 1969. Initially written in assembly language Developed as multi-user OS. later rewritten in C in 1973 Licensed to university for educational purposes in 1974 POSIX (Portable Operating System for Unix) was developed

Unix Flavours

  • AIX by IBM
  • Solaris by Sun Microsystems
  • HP-UX by Hewlett Packard
  • IRIX by Silicon Graphics, Inc
  • FreeBSD by Free BSD Group
  • GNU/Linux by Open Source Movement
  • SCO Unix by The Santa Cruz Operation Inc

Features of UNIX

  • Multi user
  • Multi tasking
  • Interactive
  • Shell
  • Security
  • Hierarchial file system

Unix Architecture

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Unix File Systems

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