1. Operating Systems
Chapter 4

2. Chapter Objectives Define an operating system and its main functions.
List the main operating systems in use today.
Identify the features and advantages of a CLI.
Identify the features and advantages of a GUI.
Explain DOS.
Compare major operating systems.

3. Introduction to Operating Systems
Common operating systems are: Microsoft Windows, Mac OS, UNIX, Linux.
The operating system is basically the ‘manager’ of the computer
Without an operating system no other software applications could work.
The OS must manage processor resources, memory, storage, input/output and the user interface.

4. Operating System Basic Tasks
Manage Memory
Manage CPU resources
Manage Storage Resources
Control Input and Output
Establish Basic Elements of the User Interface

5. User Interfaces
A user interface can be broadly defined as the space or environment where interaction between humans and machines occurs.
A good user interface does the following:
Allows the user to manipulate a system
Allows the system to indicate the effects of the users' manipulation .

6. Two Types of Computer Interfaces
Command Line Interface (CLI)
Early computers used a command line interface that required users to type memorized commands to run programs and accomplish tasks.
Graphical User Interface (GUI)
A GUI is an interface built around visual things

7. DOS
Disk Operating System

8. DOS: Disk Operating System
DOS is an acronym for Disk Operating System.
DOS was released in 1981 by Microsoft and was a non-graphical command line operating system.
DOS is considered the first commercial operating system to be released for use on a microcomputer.

9. Graphical User Interface (GUI)
First developed in 1981
Pronounced as”gooey” or”gee you eye”
GUI uses windows, icons, and menus to execute such command such as opening files or folders, moving, copying or deleting files.
Easy to learn and use.

10. Graphical User Interface (GUI)
In 1983 Apple releases the LISA computer as the first GUI computer.

11. Graphical User Interface (GUI)
A GUI is an interface built around visual things:
Windows are areas of the screen that are used to display information or controls
Icons are small graphics that are used to represent tasks and applications.
Menus are graphical boxes that list options the user can select from.
A pointer is graphic that can be moved around the screen to select tasks.

12. Graphical User Interface (GUI)
Microsoft Windows GUI

13. CLI versus GUI

14. CLI versus GUI
Because of the memorization and familiarity needed to operate a command line interface new users find it much more difficult
Users have much more control of their file system and operating system in a command line interface.
Does not offer the ability to view multiple things at once on one screen.
Command line Interface is fast.
A computer that is only using the command line takes a lot less of the computers resources.
CLI

15. CLI versus GUI GUI Easy to learn and use.
Using a mouse and keyboard to control your operating system for many things is going to be much slower than someone who is working in a command line.
A GUI will require a lot more system resources because of each of the elements that need to be loaded such as icons, fonts, etc.
GUI users have windows that enable a user to easily view, control, and manipulate multiple things at once.
GUI

16. Using a CLI Within Microsoft Windows
Easy to learn and use.
Using a mouse and keyboard to control your operating system for many things is going to be much slower than someone who is working in a command line.
A GUI will require a lot more system resources because of each of the elements that need to be loaded such as icons, fonts, etc.
GUI users have windows that enable a user to easily view, control, and manipulate multiple things at once.
GUI

17. Other Operating Systems
UNIX is a powerful OS
Originally designed for network computers
Developed by Bell Labs in 1960’s.
All of the most popular Operating Systems are UNIX based with the exception of MS Windows

18. Other Operating Systems
Derived from UNIX
Free to download
Open source
Powerful alternative to MS Windows

19. Other Operating Systems
MAC OS X
Mac OS X is Apple’s current OS
Its interface is built on a UNIX foundation
This OS has improved stability, security and performance
It is a great alternative to Windows 7 if you are in the market for an Apple computer

20. What is the best operating system?
The Mac OS X has better security controls to limit the spread of viruses.
Apple computers are still much more expensive than other computers.
Apple computers are notoriously easy to use.
Apple computers are designed for graphics and multimedia.
Windows based computers have a wider selection of software.
Windows based computers are better for gaming.
Windows based computers do very well with graphics and multimedia.
Windows based computers are better for business application.
Windows based computers have a 90% market share.
Linux/UNIX based systems are very stable.
Linux/UNIX has many features found in other operating systems.
Linux is free and is open source.

21. What is the best operating system?
If you are in the market for a new computer or an upgraded operating system, it is suggested that you try out different operating systems at retail stores. Talk to experts and research each operating system. In the case of Linux you can download it for free from the Internet.

22. Mobile Operating Systems
A mobile operating system, also known as a mobile OS, is the operating system that controls a mobile device or other information device.

23. Mobile Operating Systems
Devices running a mobile OS include:
Smart phones
Tablet computers
Personal digital assistants

24. Mobile Operating Systems
Major companies producing Mobile OS:
Google
Apple
Nokia
RIM
Palm
Microsoft

25. Mobile Operating Systems
Most popular mobile operating systems
Google Android
Apple iOS
Blackberry OS

26. End of Chapter
Chapter Four Complete