Overview of Unix

Introduction#

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

Unix File Systems