Chapter 5 : Types of Utility Programs and Operating System

• System software consists of the programs that control or maintain the operations of the computer and its devices.
• An operating system (OS) is a set of programs containing instructions that work together to coordinate all the activities among computer hardware resources
1. Start and shut down a computer
2. Provide a user interface
3. manage programs
4. manage memory
5. Coordinate tasks
6. Configure devices
7. Establish an internet connection
8. Monitor performance
9. Provide utilities
10. Automatically update
11. Control a network
12. Administer security

Operating System Functions

• The process of starting or restarting a computer is called booting.
• COLD BOOT
• Turning on a computer that has been powered off completely.
• WARM BOOT
• Using the operating system to restart a computer.
• How a PC Boot
1. Step 1: The power supply sends a signal to the components in the system unit.
2. Step 2: The processor finds the ROM chip(s) that contains the BIOS (basic input?output system).
3. Step 3: The BIOS perform the POST(power-on self test),which checks components,such as the mouse,keyboard,and adapter cards
4. Step 4: The results of the POST are compared with data in a CMOS chip.
5. Step 5: The BIOS may look for the system files on a USB flash drive or on an optical disc drive or may look directly on drive C (hard disk).
6. Step 6: The system files and the kernel of the operating system load into memory (RAM) from storage (i.e.hard disk).
7. Step 7: The operating system loads configuration information,may request user information,starts several background processes,and displays the desktop on the screen.
• A boot drive is the drive from which your computer starts
1. You can boot from a boot disk.
2. A recovery disk contains a few system files that will start the computer.
• An operating system includes various shut down options
1. Sleep mode saves any open documents and programs to RAM, turns off all unneeded functions,and then places the computer in a low-power state.
2. Hibernate saves any open documents and programs to hard disk before removing power from the computer.
• A user interface controls how you enter data and instructions and how information is displayed on the screen.
• With a graphical user interface (GUI), you interact with menus and visual images.
• With a command-line interface,a user uses the keyboard to enter data and instructions.
• How an operating system handles programs directly affects your productivity
1. Single user and multiuser
2. Single tasking and multitasking
3. Foreground and background
4. Preemptive multitasking
5. Multiprocessing
• Memory management optimizes the use of RAM.
• Virtual memory is a portion of a storage medium functioning as additional RAM.
• The operating system determines the order in which tasks are processed
• A driver is a small program that tells the operating system how to communicate with a specific device.
• Plug and Play automatically configures new devices as you install them.
• Operating systems typically provide a means to establish internet connections.
• A performance monitor is a program that assesses and reports information about various computer resources and devices.
• Operating systems often provide users with the capability of; 
1. Managing files
2. Searching for files
3. Viewing images
4. Securing a computer
5. Uninstalling programs
6. Cleaning up disks
7. Defragmenting disks
8. Diagnosing problems
9. Backing up files and disks
10. Setting up screen savers
• Automatic update automatically provides updates to the program
• Some operating systems are designed to work with a server on a network.
• A server operating system organizes and coordinates how multiple users access and share resources on a network.
• A network administrator uses the server operating system to:
1. Add and remove users, computers, and other devices
2. Install software and administer network security
• Each user has a user account
1. A user name, or user ID, identifies a specific user
2. A password is a private combination of character associated with the user name
• Types of Operating Systems
• Stand-alone
1. DOS
2. Early Windows versions(Windows 3.x, Windows 95,Windows NT Workstation, Windows 98, Windows 2000 Professional, Windows Millennium Edition, Windows XP, Windows Vista) 
3. Windows 7
4. Mac OS X
5. UNIX
6. Linux
• Server
1. Early Windows Server versions (Windows NT Server, Windows 2000 Server, Windows Server 2003)
2. Windows Server 2008
3. UNIX
4. Linux
5. Solaris
6. NetWare
• Embedded
• An embedded operating system resides on a ROM chip on a mobile device or consumer electronic device

1. Windows Embedded CE
2. Windows Phone 7
3. Palm OS
4. iPhone OS
5. BlackBerry
6. Google Android
7. Embedded Linux
8. Symbian OS

Stand-Alone Operating Systems

• A stand-alone operating system is a complete operating system that works on a desktop computer, notebook computer, or mobile computing device
• Window 7 is the Microsoft's fastest, most efficient operating system to date and is available in multiple editions:
1. Windows 7
2. Windows 7 Home Premium
3. Windows 7 Ultimate
4. Windows 7 Professional
• provides programs such as:
1. Windows Firewall
2. Windows DVD Maker
3. Windows Media Player
4. Desktop Gadget Gallery
• Mac OS X
1. The Macintosh operating system has set the standard for operating system ease of use
2. Latest version is Mac OS X
• UNIX
• is a multitasking operating system developed in the early 1970s.
• Linux
• is an open-source, popular, multitasking UNIX-type operating system

Server Operating Systems

• Windows Server 2008
• is an upgrade to Windows Server 2003
• Part of the Windows Server 2008 family
• Multiple editions
• Most editions include Hyper-V,a virtualization technology
• Virtualization is the practice of sharing or pooling computing resources
• UNIX
• Linux
• Solaris
• Netware

Utility Programs

• A type of system software that allows a user to perform maintenance-type tasks
• A file manager is a utility that performs functions related to file management
1. Displaying a list of files
2. Organizing files in folders
3. Copying,renaming,deleting,moving,and sorting files and folders
4. Creating shortcuts
• A search utility is a program that attempts to locate a file on your computer based on criteria you specify.
• An image viewer allows users to display,copy, and print the contents of a graphics file.
• An uninstaller removes a program, as well as any associated entries in the system files.
• A disk cleanup utility searches for and removes unnecessary files
1. Download program files
2. Temporary internet files
3. Deleted files
4. Unused program files
• A disk defragmenter reorganizes the files and unused space on a computer's hard disk so that the operating system accesses data more quickly and programs run faster
• Defragmenting
• A backup utility allows users to copy files to another storage medium.
• A restore utility reverses the process and returns backed up files to their original form.
• A screen saver causes a display device's screen to show a moving image or blank screen if no activity occurs for a specified time.
• A personal firewall detects and protects a personal computer from unauthorized instrusions.
• A virus describes a potentially damaging computer program that affects a computer negatively.
• A worm copies itself repeatedly in memory or over a network.
• A Trojan horse hides within or looks like a legitimate program.
• An antivirus program protects a computer against viruses.
• Spyware is a program placed on a computer without the user's knowledge that secretly collects information about the user.
• A spyware remover detects and deletes spyware and other similar programs.
• Adware displays on online advertisement in a banner or pop-up window.
• An adware remover is a program that detects and deletes adware.
• Filters are programs that remove or block certain items from being displayed
1. Web filtering software
2. Anti-spam programs
3. Phishing filters
4. Pop-up blockers
• A  file compression utility shrinks the size of a file(s)
• Compressing files frees up room on the storage media
• Two types of compression
1. Lossy
2. Lossless
• Compressed files sometimes are called zipped files
• can be uncompressed
• A media player allows you to view images and animation, listen to audio,and watch video files on your computer.
• Disc burning software writes text,graphics, audio,and video files on a recordable or rewritable optical disc.
• A personal computer maintenance utility identifies and fixes operating system problems,detects and repairs disk problems, and includes the capability of improving a computer's performance.