Architecture of Linux Operating System

• Kernel

The Linix kernel includes devices driver support for a large number of PC
hardware devices, advanced processor and memory management features, and
support for many different types of filesystems .

• Shells and GUIs

Linux supports two froms of command input: through textual command line shells similar to those found on most UNIX systems.(e.g. sh-the Bourne shell, Bash- the Bourne again shell and csh- the c shell) and through graphical inteface (GUIs) such as the KDE and GNOME window managers.

• System utilities
  

Virtually every systems utility that you would expect to find on standrad implementations of UNIX has been ported to Linux. This includes commands such as ls,cp,grep,awk,sed,bc,wc,more, and so on.

• Application programs

Linux distributors typically come with several useful application programs as standrad.

Linux Distributor

As Linux has become more popular, several different development streams or distributors have emerged, e.g.Redhat, slackware, Mandrake, Debian, and Cladera. A distribution compries a prepackaged kernel, system utilities, GUI interface and application programs.

Redhat is the most popular distribution because it has been ported to a large number of hardware platfroms, it is easy to use install and it comes with a comprehensive set of utilities and applications including the X windows graphics system, GNOME and KDE GUI environments, and the staroffice suite.

Open Source Nature of Linux

The open source nature of linux means that the source code for the linux kernel is freely available so that anyone can ad features and correct deficiencies.This approach has been very successful and what started as one persons project has now turned into a collaboration of hundreds of volunteer developers from around the globe. The open source approach has not just successfully been applied to kernel code, but also to application programs for linux.

A Brief History of UNIX

UNIX has been a popular OS for more then two decades because of its multi-user, multi-tasking environment,Stability, Portability and powerful networking capabilities.What follows here is a simplified history of how UNIX has develop.

What is an operaitng system ?

An operating operating system is a resource manager. It takes the form of a set of software
Routines that allow users and application programs to access system resources in a safe,efficient and abstract way.