Computers Tools for an Information Age Chapter 3 Operating Systems Software in the Background Objectives of Chapter 3 Describe the functions of an Operating System Explain the basics of a personal computer operating system Describe the advantages of a graphical operating system Differentiate among different operating systems Explain the need for network operating systems Describe the methods of resource allocation on large computers Be able to describe the differences among multiprocessing multiprogramming and timesharing Explain the principles of memory management List several functions typically performed by utility programs Systems Software Definition All programs related to coordinating computer operations Components Operating System Utility programs Program language translators Operating Systems Hidden Software Serves as intermediary between hardware and applications software User interested in application software to make the PC useful Application software is platform specific User must be aware of the type of OS User should be aware of the functions of OS Operating System The set of programs that lies between applications software and the hardware and Manages computer s resources CPU memory peripheral devices Establishes a user interface Determines how user interacts with operating system Provides and executes services for applications software Kernel Manages the operating system Loaded from hard drive into memory when computer is booted Booting refers to starting the computer Loads other operating system programs from disk storage as needed Other programs referred to as nonresident User Interface Facilitates communication between the user and the operating system Two forms Command line Text based Key commands Examples MS DOS Unix Graphical user interface GUI pronounced gooey Visual images Menus Examples X Windows UNIX MS Windows Mac OS Platform Definition Computer hardware and operating system software that dictate what other software can run Wintel Windows Intel Intel based PC running MS Windows SPARC Sun Microsystems Sun based architecture running Solaris UNIX Types of Operating Systems Interface Single User PC MAC Multi user Command Line GUI UNIX Linux Mainframe Proprietary Network ed Operating System NOS Operating Systems for Personal Computers Platform combination of computer hardware and operating system software Wintel Microsoft Windows running on an Intel based PC is most common Common Platforms MS DOS Windows MAC OS Unix Linux MS DOS Uses a command line interface Screen provides prompts for user User types commands Largely replaced by graphical user interfaces Not user friendly Microsoft Windows Began as an operating environment for MS DOS Uses a graphical user interface Not a full blown operating system required MS DOS Users can use DOS commands and interface Now a complete family of operating systems MS DOS Operating Environment Windows 3 1 A layer added on top of DOS Separates operating system from user Makes operating system easier to use Called a shell Graphical User Interface Eases access to the OS Most new computers come with Windows already installed GUI Graphical User Interface Aka WIMP interface On screen pictures Windows Icons Menus Pointer Icons Menus Pull down Pop up Click to activate a command or function Fast and Easy Intuitive usually Windows Features Long file names up to 255 characters Plug and Play Makes installing hardware components easier Object Linking and Embedding OLE Allows user to embed or link one document to another The Windows Family Windows 9x Corporate Market Windows 95 Windows 98 Windows Millennium Edition ME Windows NT Windows 2000 Windows XP Windows CE Windows 9x Serves home consumer market No longer a shell but a self contained operating system Began with Windows 95 Next Generation Windows 98 Windows ME Many improvements over Windows 3 1 Windows 98 Enhancements Internet intranet browsing capabilities Support for state of the art hardware including DVD and multimedia Support for larger disk drives Wizards step by step software for installing configuring and using software Windows ME Enhancements Multimedia support Media Player video editing Enhanced reliability features Home network support Corporate Market Windows NT NT stands for new technology Windows 2000 Windows NT Desktop looks and acts like Windows 98 Meant for corporate networked environments Engineered for scalability the ability to handle many users Stronger security Windows 2000 The latest generation of Windows NT One computer serves many users You identify yourself and the system knows your preferences You get your desktop and files regardless of which PC you use to log into the network Windows XP Brings consumer and corporate versions of Windows together into a single product Has Home and Professional Editions Windows XP Enhancements Improved user interface Improved multimedia support More personalization Multiple user support Much clearer and uncluttered desktop More icons on redesigned Start Menu User can log off leaving programs running and allow another user to log on Set up limited accounts for children to use i e no inappropriate games or no Internet access Internet support and protection Windows CE Scaled back version of Windows 9x Used in Pocket PCs Used in embedded systems Designed to work on machines with small screens and little if any storage Computer devices integrated into other products i e robots CE NET supports NET platform MAC OS Designed for the Macintosh computer First commercially successful GUI Has served as the model for Windows and other GUI products developed since then UNIX Developed in 1971 for use on the DEC minicomputer Character based system with command line interface Not tied to any family of processors Runs on just about every type of system PC mainframe workstation from any manufacturer Primary operating system in use on Internet servers Handles many simultaneous users easily Free BSD A Free public domain version of Berkeley UNIX Open source software GNU General Public License Download it free www freebsd org Make changes and use freely XFree86 GUI included PC Setup PC comes with Windows installed Install FreeBSD in a dual boot configuration or reformat drives and use only FreeBSD Linux Uses command line interface Open source concept Many companies have created a GUI to work with Linux Source code is free Users can download change and distribute the software More stable than Windows Applications relatively scarce PC Setup PC comes