Chapter 8

Utility Program

STARTING A COMPUTER

The process of starting or resetting a computer involves loading an operating system into memory ‑ a process called booting the computer. When you turn on a computer after it has been powered off completely, you are performing a cold boot. A warm boot, by contrast, is the process of restarting, or resetting, a computer that already is on. When using Windows, you typically can perform a warm boot, also called a warm start, by pressing a combination of keyboard keys (CTRL+ALT+DEL), selecting options from a menu, or pressing a Reset button on your computer.

When you boot a computer, information displays on the screen (Figure 8‑19). The actual information displayed varies depending on the make of the computer and the equipment installed. The boot process, however, is similar for large and small computers.

The following steps explain what occurs during a cold boot for a personal computer using the Windows operating system.

1. When you turn on your computer, the power supply sends an electrical signal to the motherboard and the other devices located in the system unit.

2. The surge of electricity causes the CPU chip to reset itself and look for the ROM chip(s) that contains the BIOS. The BIOS (pronounced BYE‑oss), which stands for basic input/output system, is firmware that contains the computer's startup instructions. Recall that firmware consists of ROM chips that contain permanently written instructions and data.

3. The BIOS begins by executing a series of tests to make sure the computer hardware is connected properly and operating correctly. The tests, collectively called the power‑on self test (POST), check the various system components such as the buses, system clock, expansion cards, RAM chips, keyboard, floppy disk drive(s), and hard disk. As the POST is performed, LEDs flicker on devices such as the disk drives and keyboard, several beeps sound, and messages display on the monitor's screen.

4. The results of the POST are compared with data in a CMOS chip on the motherboard. Recall that the CMOS chip stores configuration information about the computer, such as the amount of memory; type of disk drives, keyboard, and monitor; the current date and time; and other startup information needed when the computer is turned on. The CMOS chip is updated whenever new components are installed. If any problems are found, the computer may beep, display error messages, or cease operating — depending on the severity of the problem.

5. If the POST is completed successfully, the BIOS looks for the boot program that loads the operating system. Usually, it first looks in drive A (the designation for a floppy disk drive). If an operating system disk is not inserted into drive A, the BIOS looks in drive C, which is the designation usually given to the first hard disk. If neither drive A nor drive C contain the boot program, some computers look to the CD‑ROM drive.

6. Once located, the boot program is loaded into memory and executed. The boot program then loads the kernel of the operating system into RAM. The operating system takes control of the computer.

7. The operating system loads system configuration information. In Windows, system configuration information is contained in several files called the registry. Windows constantly accesses the registry during the computer's operation for information such as installed hardware and software devices and individual user preferences for mouse speed, passwords, and other user‑specific information.

For each hardware device identified in the registry, such as the sound card, a CDROM or DVD‑ROM drive, or a scanner, the operating system loads a device driver. Recall that a device driver is a program that tells the operating system how to communicate with a device.

 The remainder of the operating system is loaded into RAM and the desktop and icons display on the screen. The operating system executes programs in the StartUp folder, which contains a list of programs that open automatically when you boot your computer.

Boot Disk

Under normal circumstances, the drive from which your computer boots, called the boot drive, is drive C (the hard disk). If you cannot boot from the hard disk, for example if it is damaged or destroyed, you can boot from a boot disk. A boot disk is a floppy disk that contains certain operating system commands that will start the computer. For this reason, it is crucial you have a boot disk available— ready for use at any time.

When you install an operating system, one of the installation steps involves making a boot disk. You may not, however, have a boot disk because the operating system was pre‑installed by the computer's manufacturer when you purchased the computer. If you do not have a boot disk, you should create one and keep it in a safe place. The steps in Figure 8‑21 show how to create a boot disk in Windows 98.

UTILITY PROGRAMS

A utility program, also called a utility, is a type of system software that performs a specific task, usually related to managing a computer, its devices, or its programs. Most operating systems include several utility programs. As shown in Figure 8‑22, for example, Windows 98 provides access to many utility programs through the System Tools submenu. You also can buy stand‑alone utilities that offer improvements over those supplied with the operating system.

Popular utility programs perform these functions: viewing files, compressing files, diagnosing problems, scanning disks, defragmenting disks, uninstalling software, backing up files and disks, checking for viruses, and displaying screen savers. Each of these utilities is briefly discussed in the following paragraphs.

��	A file viewer is a utility that displays the contents of a file. An operating system's file manager often includes a file viewer. In Windows 98, for example, Windows Explorer has two viewers: one called Quick View to display the contents of text files and another called Imaging Preview for graphics files (Figure 8‑23). The title bar of the file viewer window displays the name of the file being viewed.

��	A file compression utility reduces, or compresses, the size of a file. A compressed file takes up less storage space on a hard disk or floppy disk, which frees up room on disk and improves system performance. Files available for download from the internet often are compressed to reduce download time. Compressing files attached to e-mail messages also reduces the time needed for file transmission.

		Because compressed files usually have a .zip extension, compressed files sometimes are called zipped files. When you receive a compressed file, you must uncompress, or unzip, the file or restore it to its original form. Two popular stand‑alone file compression utilities are PKZIP and WinZip.

��	A diagnostic utility compiles technical information about your computer’s hardware and certain system software programs and then prepares a report outlining any 1dent~fied problems. For example, Windows 98 includes the diagnostic utility, Dr. Watson which diagnoses problems as well as suggests courses of action.

��	A disk scanner is a utility that (1) detects and corrects both physical and logical problems on a hard disk or floppy disk and (2) searches for and removes unwanted files. A physical problem is one with the media, such as a scratch on the surface of the disk. A logical problem is one with the data, such as a corrupted file allocation table (FAT). Windows 98 includes two disk scanner utilities: ScanDisk, which detects and corrects problems, and Disk Cleanup, which searches for and removes unnecessary files such as temporary files.

��	A disk defragmenter is a utility that reorganizes the files and unused space on a computer's hard disk so data can be accessed more quickly and programs can run faster. When a computer stores data on a disk, it places the data in the first available sector on the disk. Although the computer attempts to place data in sectors that are contiguous (next to each other), this is not always possible. When the contents of a file are scattered across two or more noncontiguous sectors, the file is fragmented. Fragmentation slows down disk access and thus the performance of the entire computer. The process of defragmentation—that is, reorganizing the disk so the files are stored in contiguous sectors—solves this problem. Windows 98 includes a disk defragmenter, called Disk Defragmenter.

��	  An uninstaller is a utility that removes an application, as well as any associated entries in the system files (Figure 8‑28). When you install an application, the operating system records the information that it uses to run the software in the system files. If you attempt to remove the application from your computer by deleting the files and folders associated with that program without running the uninstaller, the system file entries remain. Most operating systems include an uninstaller; you also can purchase a standalone program, such as CyberMedia's UnInstaller.

��	A backup utility allows you to copy, or backup, selected files or your entire hard disk onto another disk or tape. During the backup process, the backup utility monitors progress and alerts you if additional disks or tapes are needed. Many backup programs will compress files during this process, so the backup files require less storage space than the original files.

	For this reason, backup files usually are not usable in their backed up form. In the event you need to use one of these files, a restore program, which is included with the backup utility, reverses the process and returns backed up files to their original form. You should back up files and disks regularly in the event your originals are lost, damaged, or destroyed. Windows 98 includes a backup utility, which also includes a restore program.

��	An anti-virus program is a utility that prevents, detects, and removes viruses from a computer's memory or storage devices. A virus is a program that copies itself into other programs and spreads through multiple computers. Viruses often are designed to damage a computer intentionally by destroying or corrupting its data.

��	A screen saver is a utility that causes the monitor's screen to display a moving image or blank screen if no keyboard or mouse activity occurs for a specified time period (Figure 8‑30). When you press a key on the keyboard or move the mouse, the screen returns to the previously displayed image.

Screen savers originally were developed to prevent a problem called ghosting, in which images could be permanently etched on a monitor's screen. Although ghosting is not a problem with today's monitors, screen savers stil1 are used for reasons of security, business, or entertainment. To secure a computer, for example, you can configure your screen saver so that you must enter a password to stop the screen saver and redisplay the previous image. Some screen savers use push technology so you receive updated and new information each time the screen saver displays.