2. Jozef Goetz, 2009 1 1 My Lecture Notes Have tutorial values Comply with research-based principles for design Power Point presentation Concepts are presented visually with many diagrams and pictures. They use visual aids (diagrams, pictures etc.) and pictures are presented near each other on the page or screen. The context is presented in the hierarchical way, details are indented Important key words are highlighted or written in different color

3. Jozef Goetz, 2009 2 expanded by Jozef Goetz, 2008 Credits: Parts of the slides are based on slides created by textbook authors, Syed M. Sarwar, Robert Koretsky, Syed A. Sarwar

4. Jozef Goetz, 2009 3 Objectives To explain what an operating system is To describe briefly operating system services To describe character and graphical user interfaces - GUI To discuss different types of operating systems To briefly describe the LINUX operating system To describe briefly the history of the LINUX operating system To provide an overview of the different types of LINUX systems

5. Jozef Goetz, 2009 4 What is an Operating System? Primary purpose is to facilitate: Easy, efficient, fair, orderly and secure use of hardware and software resources. Allows users to employ application software, language libraries, system calls and program generation tools. Two ways of viewing an operating system: Top-down – user view E.g., The OS performs the task of dealing with complicated hardware resources and gives you a comprehensive and simple machine, ready to use. In this way the OS provides a virtual machine Bottom up – system view E.g., the OS decides how much space how much RAM space is to be allocated to a program before it is loaded and executed, use commands such as cp memo myLetters In this was the OS can be viewed as a resource manager.

6. Jozef Goetz, 2009 5 Layered View of a Computer System App. User’s Interface App. Programmer's Interface

7. Jozef Goetz, 2009 6 Operating System Services 1. Communication between processes Process control Create, terminate processes Allocate and free memory 2. Execution of a program 3. Input and output operations performed by programs Device management 4. Manipulation of all types of files File management 5. Management of users and security 6. Error detection and reporting

8. Jozef Goetz, 2009 7 Character Versus Graphical User Interface. Character (Command Line) User Interface – CUI or CLI Input device (e.g., Keyboard is used to issue a command) Efficient A minimal layer of software is needed between you and your task on computer

9. Jozef Goetz, 2009 8 Character Versus Graphical User Interface. Graphical User Interface - GUI Input is taken from a point-and-click device. Most popular desktop environments GNU (pronounced /gnu/) is a computer operating system composed entirely of free software.pronounced/gnu/operating systemfree software Its name is a recursive acronym for GNU's Not Unix, which was chosen because its design is Unix-like, but differs from Unix by being free software and by not containing any Unix code.recursive acronymUnix-likeUnix GNU was founded by Richard StallmanRichard Stallman GNU - A set of programs written by the Free Software Foundation to provide a Free UNIX framework. GNU is a large component of a Linux distribution. Variants of the GNU operating system, which use the kernel called Linux, are now widely used; though these systems are often referred to as “Linux”, they are more accurately called GNU/Linux systems.GNU/Linux systems GNU Network Object Model Environment – GNOME K Desktop Environment - KDE

10. Jozef Goetz, 2009 9 Types of Operating Systems 1. Single-user, single-process system (e.g. DOS) 2. Single-user, multiprocess system 3. Multiuser, multiprocess system 1. The CPU can be moved from one process to another process - multiprogramming 2. multiprocess system increases resource utilization and system throughput 4. Time-sharing systems - Multiuser, multiprocess and interactive operating system OS 1. The CPU is switched from one process to another giving the impression of sole use of the system

11. Jozef Goetz, 2009 10 The Development of the UNIX Operating System Research Operating System UNIX Version 1 through UNIX Version 6 Developed and Written in C Releases distributed as C Source Code The design of the system allowed users to run multiple processes concurrently and to connect these processes with streams. AT& T System V Released in 1983 Berkley Software Distributions 3BSD and 4BSD The History of Shells Bourne Shell, C Shell, Korn Shell. Current and Future Developments - UNIX

12. Jozef Goetz, 2009 11

13. Jozef Goetz, 2009 12 Web Resources

14. Jozef Goetz, 2009 13 What is Linux? Linux is a clone of the operating system Unix, written from scratch by Linus Torvalds ’91 with assistance from a loosely-knit team of hackers across the Net.

15. Jozef Goetz, 2009 14 Table 2.1 Web Resources (continued on next slide) http://www.linuxbase.org/

16. Jozef Goetz, 2009 15 Table 2.1 Web Resources (continued from previous slide)

17. Jozef Goetz, 2009 16 Table 2.2 Major LINUX Distributions Top Ten Distributions as of 11/19/09: http://distrowatch.com/dwres.php?resource=major http://distrowatch.com/dwres.php?resource=major

18. Jozef Goetz, 2009 17 Distribution of Linux If you're new to Linux, you don't want to download the kernel - a component in a working Linux system. Instead, you want what is called a distribution of Linux, which is a complete Linux system there are over 250 varieties of LINUX There are numerous distributions available for download on the Internet as well as for purchase from various vendors http://www.linuxiso.org/http://www.linuxiso.org/ some are general-purpose, and some are optimized for specific uses. mirrors of several distributions available at mirrors.kernel.org mirrors.kernel.org To install Linux visit http://www.linux.org/docs/beginner/install.html http://www.linux.org/docs/beginner/install.html

19. Jozef Goetz, 2009 18 Linux growth http://www.linuxdevices.com/http://www.linuxdevices.com/ - Linux related articles http://www.apache.com/http://www.apache.com/ - Apache’s projects Web site http://www.gnu.orghttp://www.gnu.org - GNU website Linux growth in 2004 - 2.5x the unit growth of all other major commercial operating environments combined - Triple the revenue growth of all other major commercial operating environments combined IBM is the Linux market leader - 30% share vs. HP at 26% and vs. Dell at 15% - Took market share from both HP and Dell in Linux x86 revenue in 2004 (surpassing Dell for the first time) Linux in 2005 New 2.6 kernel addresses both scalability and linear performance issues Linux 2.6.32 as 11/14/2009

20. Jozef Goetz, 2009 19 Linux growth Reliability remains outstanding - Note: reliability is highly dependent on systems manufacturer Availability/failover extensions can now be readily found failover - the transfer of operation from a failed component (e.g., controller, disk drive) to a similar, redundant component to ensure uninterrupted data flow and operability LINUX can be received: - From Linux suppliers such as Red Hat, Novell (SuSE), or other United Linux suppliers - From traditional hardware/software vendors such as Sun and IBM - From point product failover software makers - From grid suppliers (in the form of distributed resource management software)

21. Jozef Goetz, 2009 20 Linux growth Linux is, today, a solid enterprise-class environment with a rich infrastructure ecosystem Needs improvement in packaged applications support value Linux over Windows in terms of security, low cost, and reliability.” Red Hat Enterprise Linux is the leading platform for open source computing. It is sold by subscription, delivers continuous value and is certified by top enterprise hardware and software vendors. From the desktop to the datacenter, Enterprise Linux couples the innovation of open source technology and the stability of a true enterprise-class platform. The Fedora Project (2002-2005) is a Red Hat sponsored and community-supported open source project with the goal of working with the Linux community to build a complete, general purpose OS exclusively from free software.