important to me?
Utility programs, also known as ser- vice programs, perform tasks related to the control and allocation of computer resources. They enhance existing functions or provide services not supplied by other system software programs. Most computers come with
built-in utilities as part of the system software. However, they may also be bought separately as external utility programs (such as Norton SystemWorks and McAfee Utilities).
Among the tasks performed by utilities are backing up data, compressing files, recovering lost data, and identifying hardware problems. (See below.)
U
tility programs are incorporated into the operating system. Others, such as antivirus programs, are sold as stand-alone programs. Some important utility programs are as follows:Backup
Suddenly your hard-disk drive fails, and you have no more programs or files. Fortunately, we hope, you have used a backup utility to make a backup, or duplicate copy, of the information on your hard disk. The backup can be made to
PRACTICAL ACTION
Utility Programs
an external hard drive, an off- site networked (online) site, or other choices discussed later in the book. Examples of freestanding backup utili-
ties are Norton Ghost (from Symantec) and DT Utilities PC Backup.
Data Recovery
One day in the 1970s, so the story goes, programming legend Peter Norton was working at his computer and accidentally
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Survival Tip
Temp File Removal
In Windows, to remove tem- porary and unnecessary files from your hard drive, Click Start, All Programs, Acces- sories, System Tools, and Disk Cleanup. Put checks in the boxes next to the types of file you want to delete, and click OK.
deleted an important file. This was, and is, a common enough error. However, instead of reentering all the information, Norton decided to write a computer program to recover the lost data. He called the program “The Norton Utilities.” Ulti- mately it and other utilities made him very rich.
A data-recovery utility is used to restore data that has been physically damaged or corrupted. Data can be dam- aged by viruses (see following), bad software, hardware fail- ure, and power fluctuations that occur while data is being written/recorded.
Virus Protection
If there’s anything that can make your heart sink faster than the sudden failure of your hard disk, it may be the realiza- tion that your computer system has been invaded by a virus.
A virus consists of hidden programming instructions that are buried within an application or system program. Sometimes viruses copy themselves to other programs, causing havoc.
Sometimes the virus is merely a simple prank that pops up in a message. Other times, however, it can destroy programs and data and wipe your hard disk clean. Viruses are spread when people exchange disks or CDs, download information from the internet and other computer networks, or open files attached to email. (
•
See Panel 3.5 .)You must, therefore, install antivirus software. Antivirus software is a utility program that scans all disks and mem- ory to detect viruses. Some utilities destroy the virus on the spot. Others notify you of possible viral behavior. Because new viruses are constantly being created, you need the type of antivirus software that can detect unknown viruses.
Examples of antivirus software are Symantec’s Norton Anti- Virus, Bit Defender, Avast!, and McAfee’s VirusScan. New viruses appear every day, so it’s advisable to look for an antivirus utility that offers frequent online updates without additional cost.
We discuss viruses again in more detail in Chapter 6.
Data Compression
As you continue to store files on your hard disk, it will even- tually fill up. You then have several choices: You can delete
old files to make room for the new. You can buy a new hard-disk cartridge drive and some cartridges and transfer the old files and programs to those. Or you can use a data com- pression utility, such as PK Zip, ZipIt, WinZip, or StuffIt. (As a result of the name “Zip,” people have come to refer to com- pressing a file as “zipping”
and decompressing a file as “unzipping.”)
Data compression utilities remove redundant ele- ments, gaps, and unnecessary data from a computer’s storage space so that less space (fewer bits) is required to store or transmit data. With a data compression utility, files can be made more compact for storage on your hard- disk drive. Given today’s huge-capacity hard drives, you may never fill yours up. Still, data compression remains an issue.
With the increasing use of large graphic, sound, and video files, data compression is necessary both to reduce the storage space required and to reduce the time required to transmit such large files over a network.
As the use of sophisticated multimedia becomes com- mon, compression and decompression are being increas- ingly taken over by built-in hardware boards that specialize in this process. That will leave the main processor free to work on other things, and compression/decompression software utilities will become obsolete.
File Defragmentation
Over time, as you delete old files from your hard disk and add new ones, something happens: The files become frag- mented. Fragmentation is the scattering of portions of files about the disk in nonadjacent areas, thus greatly slowing access to the files.
When a hard disk is new, the operating system puts files on the disk contiguously (next to one another). How- ever, as you update a file over time, new data for that file is distributed to unused spaces. These spaces may not be contiguous to the older data in that file. It takes the operat- ing system longer to read these fragmented files. A defrag- menter utility program, commonly called a “defragger,” will find all the scattered files on your hard disk and reorganize them as contiguous files. Defragmenting the files will speed up the drive’s operation.
Disk Scanner (ScanDisk or Check Disk) & Disk Cleanup
These utilities detect and correct certain types of common problems on hard drives and CDs and search for and remove unnecessary files, such as temporary files, or “temp files.”
Both Windows and the applications you run create temp files needed only for short tasks and system restore (return to normal operating conditions) after certain types of sys- tem problems. These files are stored in the Temp folder. For example, when you create a word document, Word will store a temp file version of it in the Temp folder. When you save this document, Word will save it to the location you desig- nated and delete the temp file. The computer should delete temp files when a program is closed, but this doesn’t always happen. Also, files will be left in the Temp folder if the com- puter crashes. Thus temp files can accumulate in the Temp folder and take up space.
Many other utilities exist, such as those for transfer- ring files back and forth between a desktop microcom- puter and a laptop and for troubleshooting various types
Software 129 of system problems. Generally, the companies selling
utilities do not manufacture the operating system. OS developers usually eventually incorporate the features of a proven utility as part of their product. (Note: Indepen- dent, or external, utilities must be compatible with your system software; check the software packaging and user documentation.)
For some unusual utili- ties, go to:
NimiVisuals www.mynimi.net Defraggler www.defraggler.com FileAlyzer www.safer-networking.
org/en/filealyzer
Edgeless www.fxc.btinternet.
co.uk/assistive.htm Fences www.stardock.com/
products/fences
MaxiVista www.maxivista.com FreeOTFE www.freeotfe.org DoubleKiller www.bigbang enterprises.de/en/doublekiller JPEGsnoop www.impulseadven ture.com/photo/jpeg-snoop.html
MarxioTimer www.marxio-tools.net/en/marxio-times.htm Edison www.verdiem.com/edison.asp
panel 3.5
Preventing viruses
3.4 COMMON FEATURES OF THE USER INTERFACE
What are some common features of the graphical software environment, and how do they relate to the keyboard and the mouse?
The first thing you look at when you call up any system software on the screen is the user interface — the user-controllable display screen that allows you to communicate, or interact, with the computer. Like the dashboard on a car, the user interface has gauges that show you what’s going on and switches and buttons for controlling what you want to do. From this screen, you choose the application programs you want to run or the files of data you want to open.
Survival Tip
Free Antivirus Software
For a list of free antivirus soft- ware, see:
www.thefreecountry.com/
security/antivirus.shtml
info!
morePC Tune-Up: Stop at the Pitstop
To find out what problems your PC has and to learn which utili- ties might improve its perfor- mance, go to:
www.pcpitstop.com/default.asp and try their free computer scans.
• If you download or install software from a network server (including the internet), bulletin board, or online service, always run virus scanning software on the directory you place the new files in before executing them.
• Make sure you have a disk (e.g., CD) with your virus program.
• Do not open any email from unknown sources.
• Do not open email attachments from unknown sources.
• Scan files attached to email before you open them.
• If your internet connection is always on (for example, if you have a cable modem), purchase special software called firewall software to keep other internet users out of your computer.
• Never start your computer from an unknown floppy disk. Always make sure your floppy-disk drive is empty before turning on or restarting your computer.
• Run virus-scanning software on a new floppy disk or CD before executing, installing, or copying its files into your system.
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panel 3.6
Keyboard functions