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Chapter 8 Operating Systems And Utility Programs






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    Chapter 8 Operating Systems And Utility Programs Chapter 8 Operating Systems And Utility Programs Presentation Transcript

    • Chapter 8 Operating Systems and Utility Programs
    • Chapter 8 Objectives Describe the two types of software Understand the startup process for a personal computer Describe the term user interface Explain features common to most operating systems Know the difference between stand-alone operating systems and network operating systems Identify various stand-alone operating systems Identify various network operating systems Recognize devices that use embedded operating systems Discuss the purpose of the following utilities: file viewer, file compression, diagnostic, uninstaller, disk scanner, disk defragmenter, backup, and screen saver p.8.2 Next
    • System Software
      • What is software?
      • The series of computer-language coded instructions that tells the computer how to perform tasks
      • Two types of software
      p.8.2 Next application software system software
    • System Software
      • What is system software?
      • Consists of the programs that control the operations of the computer and its devices
      • Serves as the interface between the user, the application software, and the computer's hardware
      • Two types are operating systems and utility programs
      p.8.2 Next
    • Operating Systems
      • What is an operating system (OS)?
      • A set of programs containing instructions that coordinate all the activities among computer hardware resources
      • Required for a computer to work
      • Sometimes called the software platform or platform
      p.8.3 Click to view animation Operating System Next
    • Operating Systems
      • What are the functions of an operating system?
      p.8.3 Fig. 8-1 Operating System manage programs Next start up the computer administer security control a network monitor performance and provide housekeeping services access the Web schedule jobs and configure devices provide user interface manage memory
    • Operating Systems
      • Where is the operating system located?
      • Resides on computer’s hard disk in most cases
      • May reside on a ROM chip on handheld computers
      p.8.3 Next various operating systems often are not compatible with each other same types of computers may have different operating systems different sizes of computers typically use different operating systems
    • Operating Systems
      • What is a cross-platform application?
      • One that runs identically on multiple operating systems
      • Often has multiple versions, each corresponding to a different operating system
      p.8.4 Fig. 8-2 Next runs on Windows 98 and Windows NT
    • Operating System Functions
      • What is booting?
      • The process of starting or restarting a computer
      p.8. 4 Next cold boot Process of turning on a computer after it has been powered off completely warm boot Process of restarting a computer that is already powered on Also called a warm start
    • Operating System Functions
      • What is the kernel?
      • The core of an operating system
        • Manages memory and devices
        • Maintains the computer’s clocks
        • Starts applications
        • Assigns the computer’s resources, such as devices, programs, data, and information
      • Each time you boot a computer, the kernel and other frequently used operating system instructions are loaded
        • Loading a file means the file is copied from the hard disk to the computer's memory
      p.8. 4
      • memory resident
      • Instructions remain in memory while the computer is running
      • The kernel is memory resident
      • nonresident
      • Instructions remain on the hard disk until they are needed
      • Other parts of the operating system are nonresident
    • Operating System Functions
      • What messages display on the screen when you boot the computer?
      p.8.4 Fig. 8-3 Next sound card and CD-ROM drivers loaded message devices detected and tested total amount of memory BIOS version and copyright notice
    • Operating System Functions
      • How does a personal computer boot up?
      p.8. 5 Fig. 8-4 Step 1: The power supply sends a signal to components in the system unit. Step 1 Step 2: The processor looks for the BIOS. processor BIOS Step 2 BIOS basic input/output system Firmware that contains the computer's startup instructions Next
    • Operating System Functions Step 3: The BIOS performs the POST, which checks components such as the mouse, keyboard connectors, and expansion cards. expansion cards p.8. 5 Fig. 8-4 processor BIOS CD-ROM drive Step 3 POST power-on self test Next
    • Operating System Functions p.8. 5 Fig. 8-4 Step 4: The results of the POST are compared with data in the CMOS chip. processor BIOS CD-ROM drive CMOS Step 4 expansion cards Next CMOS chip Stores configuration information about the computer Also detects new devices connected to the computer
    • Operating System Functions p.8. 5 Fig. 8-4 Step 5: The BIOS looks for the system files in drive A (floppy disk drive) and then drive C (hard disk). processor BIOS hard disk CD-ROM drive CMOS floppy disk drive Step 5 expansion cards Next system files Specific operating system files loaded during start up
    • Operating System Functions p.8. 5 Fig. 8-4 Step 6: The boot program loads the kernel of the operating system into RAM from storage (hard disk). The operating system in memory takes control of the computer. processor BIOS hard disk CD-ROM drive (RAM) memory modules CMOS floppy disk drive Step 6 expansion cards Next
    • Operating System Functions p.8. 5 Fig. 8-4 Step 7: The operating system loads configuration information and displays the desktop on the screen. The operating system executes programs in the StartUp folder. Step 7 Next registry Several files that contain the system configuration information Registry is constantly accessed during the computer's operation StartUp folder Contains a list of programs that open automatically when you boot the computer
    • Operating System Functions
      • What is a boot drive?
      • The drive from which your personal computer boots (starts)
      • In most cases, drive C (the hard disk) is the boot drive
      p.8.6 Fig. 8-5 Next
    • Operating System Functions
      • What is an emergency repair disk?
      • A floppy disk, Zip ® disk, or CD-ROM that contains system files that will start the computer
      • Used when a hard disk becomes damaged and the computer cannot boot
      • Also called a boot disk or a rescue disk
      • To create a boot disk:
      Step 1: Click the Start button on the taskbar, point to Programs on the Start menu, point to Accessories on the Programs submenu, point to System Tools on the Accessories submenu, and then point to Backup. p.8.6 Fig. 8-5 Next Step 2: Click Backup on the System Tools submenu to open the Backup window. Point to the Emergency Repair Disk button. Emergency Repair Disk button Step 3: Click the Emergency Repair Disk button to create the emergency repair disk. Follow the on-screen instructions.
      • Controls how you enter data and instructions and how information displays on the screen
      Operating System Functions
      • What is a user interface?
      p.8.7 Fig. 8-6 Click to view animation Allows you to type keywords or press special keys on the keyboard to enter data and instructions Set of commands you use to interact with the computer is called the command language command-line interface commands entered by user graphical user interface (GUI) Allows you to use menus and visual images to issue commands Next
    • Operating System Functions
      • What are features of a graphical user interface?
      • Menu: a set of commands from which you can choose
      • Icon: a small image that represents a program, an instruction, a file, or some other object
      • Web pages can be delivered or pushed automatically to your screen
      p.8.8 Fig. 8-7 Next icons function as Web links Web pages pushed onto the desktop
    • Operating System Functions
      • How does an operating system manage programs?
      • Operating systems vary in capabilities
        • Number of users
        • Number of programs running at the same time
        • Number of processors
      • Management of programs directly affects user productivity
      p.8.8 Next single user/single tasking operating system Allows only one user to run one program at a time Early systems were single user
    • Operating System Functions
      • What is multitasking?
      • Allows a single user to work on two or more applications that reside in memory at the same time
      p.8.9 Fig. 8-8
      • The foreground contains the active application: the one you currently are using
      • The other programs that are running, but are not in use, are in the background
      Next background applications listed on the toolbar foreground application
    • Operating System Functions
      • What are other program management features of operating systems?
      p.8.9 Click to view animation Next multiuser Operating system enables two or more users to run a program simultaneously multiprocessing Operating system can support two or more processors running programs at the same time fault-tolerant computer Continues to operate even if one of its components fails Computer has duplicate components such as processors, memory, and disk drives
    • Operating System Functions
      • What is memory management?
      • Optimizes the use of random access memory (RAM)
      p.8.10 clears items from memory when the processor no longer requires them monitors the contents of memory Next allocates, or assigns, data and instructions to an area of memory while they are being processed
    • Operating System Functions
      • What is virtual memory (VM) management?
      • The operating system allocates a portion of a storage medium, usually the hard disk, to function as additional RAM
      p.8.10 Fig. 8-9 RAM (physical memory) disk (virtual memory) page swapped out RAM (physical memory) disk (virtual memory) Step 1: Operating system transfers least recently used data and program instructions to disk because memory is needed for other functions. page swapped in page swapped out RAM (physical memory) disk (virtual memory) Step 2: Operating system transfers data and program instructions from disk to memory when they are needed. Next
    • Operating System Functions
      • What are some virtual memory terms?
      p.8.10 Next swap file The area of the hard disk used for virtual memory paging The technique of swapping items between memory and storage thrashing When an operating system spends much of its time paging, instead of executing application software page The amount of data and program instructions that can swap at a given time
    • Operating System Functions
      • How does an operating system schedule jobs?
      • Adjusts the schedule of jobs based on their priority
      • A buffer is an area of memory or storage in which items are placed while waiting to be transferred to or from an input or output device
      p.8.10 job An operation the processor manages Next processing instructions sending information to an output device transferring items from storage to memory and from memory to storage receiving data from an input device
      • Print jobs are sent to a buffer instead of sending them immediately to the printer
      • Multiple print jobs line up in a queue within the buffer
      • A program, called a print spooler, intercepts print jobs from the operating system and places them in the queue
      Operating System Functions
      • What is spooling?
      p.8.11 Fig. 8-10 server print job print spooler print queue server jobs to be printed disk print job print spooler print queue print queue print spooler print job jobs to be printed jobs being printed server laser printer disk Next
    • Operating System Functions
      • What is a device driver?
      • A small program that tells the operating system how to communicate with a device
      • Also called a driver
      • Each device on a computer requires its own specific driver
      p.8.11 Click to view Web Link then click Device Drivers device driver Next
    • Operating System Functions
      • How do you install a device driver?
      p.8.12 Fig. 8-11 Step 1: Open the Control Panel window. Point to the Add/Remove Hardware icon. Add/Remove Hardware icon Step 2: Start the Add/Remove Hardware Wizard by double-clicking the Add/Remove Hardware icon. Follow the on-screen instructions. Step 3: The Add/Remove Hardware Wizard searches for Plug and Play devices on your system. If it finds any such devices, it installs them. Step 4: If the Add/Remove Hardware Wizard cannot find any Plug and Play devices, you can select the type of device you want to install. device type selected Next Step 5: Next you select the manufacturer and model you want to install. You may be requested to insert the floppy disk, CD-ROM, or DVD-ROM that contains necessary driver files to complete the installation of the device. manufacturer selected model selected
    • Operating System Functions
      • What is Plug and Play?
      • The computer can recognize a new device and assist you in its installation by loading the necessary drivers automatically and checking for conflicts with other devices
      • Supported by most devices and operating systems today
      p.8. 13 Click to view Web Link then click Plug and Play Next
    • Operating System Functions
      • What is an interrupt request (IRQ)?
      • A communications line between a device and the processor
      • Most computers have 16 IRQs, numbered 0 through 15
      p.8. 13Fig. 8-12
      • IRQs are assigned during installation
    • Operating System Functions
      • How does the operating system help access the Web?
      • Typically provides a means to establish Web connections
      • Some include a Web browser and an e-mail program
      p.8.13 Fig. 8-13 Next
    • Operating System Functions
      • How does an operating system monitor performance?
      • Provides a program, called a performance monitor, that assesses and reports information about various system resources and devices
      p.8.14 Fig. 8-14 Next
    • Operating System Functions
      • How does an operating system manage files?
      • Contains a program called a file manager
      • Performs functions related to storage and file management
      p.8.14 Fig. 8-15 Next
    • Operating System Functions
      • What are some file manager functions?
      p.8.15 organizing, copying, renaming, deleting, moving, and sorting files Next displaying a list of files on a storage medium checking the amount of used or free space on a storage medium formatting and copying disks creating shortcuts: an icon on the desktop that runs a program when you click it
    • Operating System Functions
      • What is formatting?
      • The process of preparing a disk for reading and writing
      • Most floppy and hard disk manufacturers preformat their disks
      • Various operating systems format disks differently
      p.8. 15 Next
    • Operating System Functions
      • What is a file allocation table (FAT)?
      • A table of information that the operating system uses to locate files on a disk
      • Defined during the formatting process
      • Lists all files, file types, and locations
      • Reformatting a disk usually erases only the file allocation table and leaves the actual files on the disk
      p.8. 15 Next
    • Operating System Functions
      • What is a network operating system?
      • An operating system that supports a network
      • Also called a network OS or NOS
      p.8.15 Fig. 8-16
      • A network is a collection of computers and devices connected together via communications media and devices
      server controls access laser printer client client client Next
    • Operating System Functions
      • What are features of a network operating system?
      • The server is the computer that controls access to the network and provides a centralized storage area
      • The other computers on the network are called clients
      p.8.15 Fig. 8-16 Next Organizes and coordinates how multiple users access and share resources on the network Resources include programs, files, and devices such as printers and drives Network administrator uses the network OS to add and remove users, computers, and other devices to and from the network
    • Operating System Functions
      • How do operating systems administer security?
      • Most multiuser operating systems allow each user to log on
      p.8.16 Fig. 8-17 log on Process of entering a user name and a password user name A unique combination of characters that identifies one specific user Also called a user ID password A combination of characters associated with the user name that allows access to certain computer resources Next
    • Operating System Functions
      • How does a network administrator use the network OS?
      • To establish permissions to resources
      • To define who can access certain resources
      • To define when they can access those resources
      • To assign passwords to files and commands to restrict access to only authorized users
      p.8. 16 Next Active Directory (AD) A feature of Windows 2000 Server that allows network administrators to manage all network information including users, devices, settings, and connections from a central environment
    • Types of Operating Systems
      • What are some characteristics of operating systems?
      p.8.17 device-independent Run on many manufacturers’ computers device-dependent One that runs only on a specific type of computer proprietary software Privately owned and limited to a specific vendor or computer model upward-compatible Written for an earlier version of the operating system, but also runs with the new version Next downward-compatible Recognizes and works with application software written for an earlier version of the operating system
    • Types of Operating Systems
      • What are three categories of operating systems?
      p.8.17 Fig. 8-18 Next
    • Stand-Alone Operating Systems
      • What is a stand-alone operating system?
      • A complete operating system that works on a desktop or notebook computer
      • Some, called client operating systems, also work in conjunction with a network operating system
      p.8.17 Next
    • Stand-Alone Operating Systems
      • What is DOS (Disk Operating System)?
      • Refers to several single user operating systems developed in the early 1980s for personal computers
      • Two more widely used versions were PC-DOS and MS-DOS, both developed by Microsoft
      • Used a command line interface and added a menu-driven interface in later versions
      commands entered by user Next
    • Stand-Alone Operating Systems
      • What is Windows?
      • Developed by Microsoft to meet the need for an operating system that had a GUI
      p.8.18 Click to view Web Link then click Windows Windows 95 A true multitasking operating system with downward compatibility for DOS and Windows 3.x Next Windows 3.x Refers to three early versions of Microsoft Windows that were operating environments with DOS An operating environment is a GUI that works in combination with an operating system to simplify its use Windows NT Workstation A client operating system that could connect to a Windows NT server Used a Windows 95 interface
    • Stand-Alone Operating Systems
      • What are features of Windows 98?
      • Upgrade to Windows 95
      • More integrated with the Internet than Windows 95
      • Included Internet Explorer, a popular Web browser
      • The file manager, Windows Explorer, had a Web browser look and feel
      • An Active Desktop ™ interface allowing icons and file names to work similar to Web links
      p.8.18 Support for the Universal Serial Bus (USB) Next Support for multimedia technologies such as DVD and Web TV ™
    • Stand-Alone Operating Systems
      • What is Windows 2000 Professional?
      • Upgrade to the Windows NT Workstation operating system
      • Complete multitasking client operating system that has a GUI
      p.8.18 Fig. 8-19 Click to view video Next
    • Stand-Alone Operating Systems
      • What are features of most Windows operating systems?
      p.8.18 FAT32 Registry Checker Next Active Desktop ™ Taskbar/toolbars Windows Explorer has a Web browser look and feel Increased speed Tune-Up Wizard Universal Serial Bus Update Wizard Multiple display support Hardware support Accessibility Settings Wizard
    • Stand-Alone Operating Systems
      • An operating system that has features specifically for the home user
      • Also called Windows Me
      • Includes multimedia features
      • What is Windows Millennium Edition (Me)?
      p.8.20 Fig. 8-21 Next
    • Stand-Alone Operating Systems
      • What is Mac OS?
      • A multitasking operating system available only for computers manufactured by Apple
      p.8.21 Fig. 8-22 Click to view Web Link then click Mac OS
      • Apple’s Macintosh operating system was the first commercially successful GUI
      • Mac OS is the current version
    • Stand-Alone Operating Systems
      • What is OS/2 Warp?
      • IBM’s GUI multitasking client operating system
      p.8.22 Fig. 8-23
      • Supports networking, the Internet, Java, and speech recognition
      • Runs programs written specifically for OS/2, as well as most programs written for DOS and Windows
    • Company on the Cutting Edge
      • Apple Computer, Inc.
      • Formed by Steven Jobs and Stephen Wozniak in 1976
      • Began with the Apple I circuit board developed in Jobs’ garage
      • The Apple II product line generated more than $1 billion in annual sales from 1977 until 1993
      • The current high-performance Power Macintosh line was introduced in 1994, followed by the iBook, the PowerMac G4, and the Mac OS X
      p.8.21 Click to view Web Link then click Apple Next
    • Network Operating Systems
      • What is a network operating system?
      • An operating system that supports a network
      • Typically resides on a server
      • Client computers on the network rely on the server(s) for resources
      p.8.22 Next
    • Network Operating Systems
      • What is Novell’s Netware?
      • A widely used network operating system designed for client/server networks
      • Has a server portion that resides on the network server and a client portion that resides on each client computer connected to the network
      p.8.22 Click to view Web Link then click Novell Next
    • Network Operating Systems
      • What is Windows 2000 Server?
      • Family of three products
        • Windows 2000 Server: operating system for the typical business network
        • Windows 2000 Advanced Server: designed for e-commerce applications
        • Windows 2000 Datacenter Server: best for demanding, large-scale applications such as data warehousing
      p.8.22 Next Windows NT server Older version developed as an operating system for client/server networks
    • Network Operating Systems
      • What is OS/2 Warp Server for E-business?
      • IBM’s network operating system
      • Designed for all sizes of business
      • Includes Netscape as its Web browser and e-mail program
      p.8.23 Next
    • Network Operating Systems
      • What is UNIX?
      • A multitasking operating system developed in the early 1970s by scientists at Bell Laboratories
      • Lacks interoperability across multiple platforms
      p.8.23 Fig. 8-24 Click to view Web Link then click UNIX
      • Several versions exist, each slightly different
      • Command-line interface
    • Network Operating Systems
      • What is Linux?
      • A popular, free, multitasking UNIX-type operating system
      p.8.24 Fig. 8-25
      • Also includes many programming languages
      • Open-source software
        • Code is available to the public
      • Some versions are command-line and others are GUI
    • Product on the Cutting Edge
      • Operating system created by Linus Torvalds
      • A free program offered as alternative to Microsoft Windows and Apple Mac OS
      • Linux’ GNU General Public License allows anyone to obtain and modify the source code and then redistribute the revised product
      • A large, friendly community of users distribute the operating system and provide an extensive number of user groups, mailing lists, newsletters, and forums
      p.8.24 Click to view Web Link then click Linux Next
    • Technology Trailblazer
      • Linus Torvalds
      • Creator and lead technical developer of the free operating system Linux
      • A native of Finland
      • Credits the high level of technology and superior educational system of Finland for giving him the advantages of being able to concentrate on his brainstorm instead of worrying about economic issues
      p.8.25 Click to view Web Link then click Linus Torvalds Next
    • Network Operating Systems
      • What is Solaris ™ ?
      • A version of UNIX
      • Developed by Sun Microsystems
      • A network operating system designed specifically for e-commerce applications
      • Can manage high-traffic accounts
      • Incorporates security necessary for Web transactions
      • Client computers use a version called CDE (Common Desktop Environment)
      p.8.25 Next
    • Embedded Operating Systems
      • What is an embedded operating system?
      • The operating system on most handheld computers and small devices
      • Resides on a ROM chip
      p.8. 25 Windows CE Pocket PC OS Palm OS ® Next
    • Embedded Operating Systems
      • What is Windows CE?
      • A scaled down Windows operating system designed for use on wireless communications devices and smaller computers
        • Handheld computers
        • In-vehicle devices
        • Web-enabled devices
      p.8. 25 Fig. 8-26 Incorporates many elements of the Windows GUI Supports color, sound, multitasking, e-mail, and Internet capabilities Next Provides for scaled-down versions of applications
    • Embedded Operating Systems
      • What is an Auto PC?
      • A device mounted onto a vehicle’s dashboard that is powered by Windows CE
      • Directed through voice commands
      • Provides information to the driver such as driving directions, traffic conditions, weather, and stock quotes, and allows the driver to access and listen to e-mail
      • Acts as a radio or an audio CD
      • Shares information with a handheld or notebook computer
      p.8. 25 Fig. 8-26 Next
    • Embedded Operating Systems
      • What is Pocket PC OS ® ?
      • A scaled-down operating system developed by Microsoft
      • Works on a specific type of handheld computer, called a Pocket PC
      • Allows access to all the basic PIM functions
      • Provides Web access
      • Supports handwriting recognition
      • Allows document creation
      p.8. 26 Fig. 8-27 Click to view video Next
    • Embedded Operating Systems
      • What is Palm OS?
      • Used in handheld computers
        • Palm from Palm, Inc.
        • Visor from Handspring ®
      • Manages data and synchronizes this information with a desktop computer
      • Some access the Internet
      p.8. 26 Next
    • Utility Programs
      • What is a utility program?
      • A type of system software that performs a specific task
      • Usually related to managing a computer, its devices, or its programs
      • Also called a utility
      • Most operating systems include several utility programs
      • You can also buy stand-alone utilities
      p.8.27 utility suites Combine several utility programs into a single package Next McAfee and Norton offer utility suites and Web-based utility services Web-based utility service You pay an annual fee that allows you to access and use a vendor’s utility programs on the Web
    • Utility Programs
      • What is a file viewer?
      • Allows you to display and copy the contents of a file
      • Windows Explorer has a viewer called Imaging Preview
      p.8.27 Fig. 8-28 Imaging Preview Next
    • Utility Programs
      • What is a file compression utility?
      • Shrinks the size of a file
      • Compressed files
        • Take up less storage space than the original files
        • Sometimes called zipped files
        • Usually have a .zip extension
      • You must uncompress a compressed file to use it
      • Two popular utilities are PKZIP ™ and WinZip ®
      p.8.28 Fig. 8-29 Next compressed file
    • Utility Programs
      • What is a diagnostic utility?
      • Compiles technical information about your computer's hardware and certain system software programs
      • Prepares a report outlining any identified problems
      • Windows includes the utility Dr. Watson
      p.8.28 Fig. 8-30 Next
    • Utility Programs
      • What is an uninstaller?
      • Removes an application, as well as any associated entries in the system files
      p.8.29 Fig. 8-31
      • When an application is installed, the operating system records information it uses to run the software in the system files
      • The uninstaller removes this information
    • Utility Programs
      • What is a disk scanner?
      • Detects and corrects both physical and logical problems on a hard disk or floppy disk
        • A physical problem is one with the media
        • A logical problem is one with the data
      • Searches for and removes unnecessary files
      • Windows includes two disk scanners
      p.8.29 Fig. 8-32 Next
    • Utility Programs
      • What is a disk defragmenter?
      • A utility that reorganizes the files and unused space on a computer's hard disk
      • Allows the operating system to access data more quickly and programs to run faster
      p.8.30 Fig. 8-33
      • Defragmenting the disk reorganizes it so the files are stored in contiguous sectors
      fragmented file The contents are scattered across two or more noncontiguous sectors of a disk fragmented disk file 1 before defragmenting disk after defragmentation process file 1 after defragmenting Next
    • Utility Programs
      • What is a backup utility?
      • Allows you to copy, or backup, selected files on your entire hard disk onto another disk or tape
      • Backup utility monitors progress of the backup process
      p.8.30 Fig. 8-34
      • Many will compress files during the process
      • A restore program reverses the process and returns backed up files to their original forms
    • Utility Programs
      • What is a screen saver?
      • Causes a monitor's screen to display a moving image or blank screen if no keyboard or mouse activity occurs for a specified time period
      • Developed to prevent ghosting, in which images could be permanently etched on a monitor’s screen; no longer a problem for modern monitors
      p.8.31 Fig. 8-35 Click to view video
      • Popular for security, business, or entertainment purposes
    • Technology Trailblazer
      • Phillip Katz
      • Developed PKZIP, a data compression utility
      • His innovative PKZIP shareware cornered the data compression market
      • PKWARE has steady annual sales of $5 million
      p.8.29 Click to view Web Link then click Phillip Katz Next
    • Summary of Operating Systems and Utility Programs
      • System software
      • Operating systems
      • Operating system functions
      • Types of operating systems
      • Stand-alone operating systems
      • Network operating systems
      • Embedded operating systems
      • Utility programs
    • Chapter 8 Complete