Lenovo PC 300GL Understanding Your Personal Computer 6267, 6277, 6287 - Page 45

Information Backup, Erased Files, Computer Viruses, pattern over the entire surface of the diskette.

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Information Backup Most of the information stored on a hard disk is contained in data files. Data files contain the information you put in the computer, such as letters and reports. You can lose data files from your hard disk for a variety of reasons. Security violations, improper handling during a move, or computer viruses can destroy stored information. To avoid losing information, make copies of the data files using storage devices such as diskette drives, tape drives, or Zip drives. Also, if you are connected to a LAN, you might be able to back up information to another computer on the LAN. Backup copies can save you time and money recovering files accidentally erased from a hard disk or lost when a hard disk drive fails. Back up your hard disks on a regular basis (daily, weekly, or monthly depending on how often the information changes). Also, back up the hard disk before moving the computer. Backup procedures differ from one operating system to another. Erased Files Erasing a file from a diskette or hard disk does not necessarily destroy the file. With the proper software tools, someone might be able to restore all or part of an erased file. An erased file, therefore, might be a security exposure if you sell your computer or give someone a diskette that once contained confidential information. The standard operating-system format commands do not remove all information from a hard disk. Low-level format programs are used for this purpose and are available from a number of software manufacturers. Diskettes are a little different. An operating-system format command writes a repeated pattern over the entire surface of the diskette. As a result, any information that was on the diskette becomes unreadable. Depending on the type of information stored, you might require additional safeguards. Computer Viruses A computer virus is a program (or instructions hidden within a program) that can "infect" files and programs on your computer. Unlike most other programs, viruses are typically designed to spread themselves. Some viruses can display a message or cause erratic screen behavior. Others are destructive, erasing or damaging files, or overloading memory and communication networks. Viruses are difficult to detect. Many stay inactive until triggered by a specified event such as a date, command, or some other operation. Some are activated when an infected program is started a specified number of times. When the symptoms of the virus appear, it Security 37

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Information Backup
Most of the information stored on a hard disk is contained in
data files
.
Data files contain
the information you put in the computer, such as letters and reports.
You can lose data files from your hard disk for a variety of reasons.
Security violations,
improper handling during a move, or computer viruses can destroy stored information.
To
avoid losing information, make copies of the data files using storage devices such as
diskette drives, tape drives, or Zip drives.
Also, if you are connected to a LAN, you might
be able to back up information to another computer on the LAN.
Backup copies can save
you time and money recovering files accidentally erased from a hard disk or lost when a
hard disk drive fails.
Back up your hard disks on a regular basis (daily, weekly, or monthly depending on how
often the information changes).
Also, back up the hard disk before moving the computer.
Backup procedures differ from one operating system to another.
Erased Files
Erasing a file from a diskette or hard disk does not necessarily destroy the file.
With the
proper software tools, someone might be able to restore all or part of an erased file.
An
erased file, therefore, might be a security exposure if you sell your computer or give
someone a diskette that once contained confidential information.
The standard operating-system format commands do not remove all information from a
hard disk.
Low-level format programs are used for this purpose and are available from a
number of software manufacturers.
Diskettes are a little different.
An operating-system format command writes a repeated
pattern over the entire surface of the diskette.
As a result, any information that was on the
diskette becomes unreadable.
Depending on the type of information stored, you might require additional safeguards.
Computer Viruses
A computer virus is a program (or instructions hidden within a program) that can “infect”
files and programs on your computer.
Unlike most other programs, viruses are typically
designed to spread themselves.
Some viruses can display a message or cause erratic screen
behavior.
Others are destructive, erasing or damaging files, or overloading memory and
communication networks.
Viruses are difficult to detect.
Many stay inactive until triggered by a specified event such
as a date, command, or some other operation.
Some are activated when an infected
program is started a specified number of times.
When the symptoms of the virus appear, it
Security
37