Linux Basics

CS 302

Outline What is Unix? What is Linux? Virtual Machine.

What is Unix?

What is Unix?

An operating system developed in the 1960s. It is multi-user and multi-tasking operating

system. The most popular varieties of UNIX are Sun

Solaris, GNU/Linux, and MacOS X. The UNIX operating system is made up of

three parts; the kernel, the shell and the programs

What is Unix (Cont.)

The Kernel : a program that manages computer resources and handles system calls.

The Shell : a command line interpreter (CLI) that acts as an interface between the user and kernel.

What is Linux?

Linux History

GNU Project: Started at 1983 by Richard Stallman. Goal: creating a UNIX-like free operating system. His vision: software should be free from

restrictions against copying or modification in order to make better and efficient computer programs.

By 1991 GNU created a lot of tools, but there was still no operating system.

Linux History (Cont.)

In 1991: Linux kernel is developed by Linus Torvalds. combining Linux kernel with the not-quite-complete

GNU system resulted in a complete free operating system called Linux.

Today’s Linux distribution consists of: Linux Kernel GNU (GNU is Not Unix) Software Software Package management Others

Linux is Open Source Software

When programmers on the Internet can read, redistribute, and modify the source for a piece of software, it evolves

People improve it, people adapt it, people fix bugs. And this can happen at a speed that, compared to conventional software development.

Linux Distributions

Various organizations package the Linux kernel and system programs as Linux distributions Such as :Ubuntu, Red Hat, and Mandriva.

Common Linux features Multiuser:

Multiple users can log in and working on the system at the same time

Multiuser systems divide computer resources among multiple users, allowing for more efficient use of these resources.

Multitasking: it is possible to have many programs running at the same time

Graphical User Interface (X Window System) Hardware support

you can configure support for almost every type of hardware that can be connected to a computer

Networking connectivity: Linux offers support for a variety of local area network boards,

modems, and serial devices.

Common Linux features (Cont.)

Application support a wide range of freeware and shareware software

is available for Linux.

Most of Linux is written in the C programming language. When written in a portable style, C programs can be moved from one platform (processor or CPU-based system) to another by simply recompiling the code.

Redhat

Virtual Machine

Virtual Machine

A virtual machine (VM) is a "completely isolated guest operating system installation within a normal host operating system“

Virtualization lets you run multiple virtual machines on a single physical machine, with each virtual machine sharing the resources of that one physical computer across multiple environments.

VMware is an example of virtual machines software