What Is a Virus?
A
computer virus is code — a program — that can be recognized and run by your
computer, causing the code to reproduce. Just like a virus in a human, the
computer virus may be innocuous, bothersome or deadly. Yet in all cases, the
virus occupies precious computer memory space. Just cycling through the
program, no matter how ineffective it may be, could impair the functions of
your legitimate applications.
Michelangelo and the Media
Computer
viruses have been around for some time, but it took a threat to corporate
environments to catch the attention of the news media. Members of the media,
seeking anyone who could distinguish a bit from a byte and string together two
coherent sentences, set the stage for the following events to unfold:
On
March 6, 1992, the 5 17th birthday of
artist Michelangelo, media sources reported a virus known as Michelangelo that
would allegedly infect more than 5 million
computers worldwide. Two months of media hype and panicked hysteria as the day
approached affected world financial markets, corporate strategic agendas and
the careers of a large number of computer industry experts.
But
the alleged virus was a dud. It affected fewer hard drives than the number that
might fail on any given day. Nevertheless, other damage was done. First, the
public concluded the peril of computer viruses did not exist. Second,
misinformation from self-serving antivirus publishers implied that publicly
available and free shareware programs were part of the problem and not the
solution.
Dispelling Myths
Hysteria
and ignorance have combined to create a vibrant industry of myth, legend and
hoaxes. But, if you know the facts, you will be in a better position to respond
effectively. Familiarize yourself with the following, a few of these
falsehoods, myths and misconceptions.
Myth:
Viruses
can be transmitted via a data file, e-mail or Web page.
Fact: Data files cannot carry viruses because such files carry data, not programs. Only an executable program file can carry a virus. But there is a catch. What you believe to be just a data file may include some legitimate executable code, and this code could be infected.
Fact: Data files cannot carry viruses because such files carry data, not programs. Only an executable program file can carry a virus. But there is a catch. What you believe to be just a data file may include some legitimate executable code, and this code could be infected.
For
example, a Microsoft Word document contains only word processing data, so it
could not be infected. But a Word template file contains a small program known
as a “macro,” that could be infected. Similarly, a simple e-mail message is
just data, but an email message that includes a Word template file could carry
a virus in that file.
Don’t your Web
browser or e-mail application to launch Word automatically when it encounters a
document. Open the application first, then read the file. This will minimize
the chance of infection from a virus intended to infect the boot sector
(start-up program) of your Word application.
Myth:
Someviruses
can escape detection by antivirus software.
Fact: Inour experience, viruses can usually be detected with properly designed — and used — virus scanning software. While perhaps not visible to the naked eye of someone viewing a directory, all known virus programs have a signature that can be differentiated from legitimate code.
Fact: Inour experience, viruses can usually be detected with properly designed — and used — virus scanning software. While perhaps not visible to the naked eye of someone viewing a directory, all known virus programs have a signature that can be differentiated from legitimate code.
Myth: Backups are useless if you back up the virus along with
the data.
Fact: You can restore important data without restoring the infected program. You will have to remove the infected files, and you probably will have to reinstall computer applications from your original software source. This can be time consuming and tedious, but it is possible.
Fact: You can restore important data without restoring the infected program. You will have to remove the infected files, and you probably will have to reinstall computer applications from your original software source. This can be time consuming and tedious, but it is possible.
Myth: Shareware, public bulletin boards and the Internet
are the source of most viruses.
Fact: This usually is not the case. New shrink-wrapped software applications are a major source of viruses. Often, new applications instruct users to turn off virus protection software before installing. Follow those instructions, but also check the software for virus infection after installing. Remember, mere connection to a bulletin board or the Internet cannot transmit a virus. You transmit a file to your computer only by choosing to.
Myth:
Antivirus
makers write viruses to stay in business.
Fact: This usually is not the case. New shrink-wrapped software applications are a major source of viruses. Often, new applications instruct users to turn off virus protection software before installing. Follow those instructions, but also check the software for virus infection after installing. Remember, mere connection to a bulletin board or the Internet cannot transmit a virus. You transmit a file to your computer only by choosing to.
Fact: They don’t need to. Legions of people have the skills and are happy to use them. Contrary to popular belief, virus creators are not limited to bored teenage hackers. They include professional business people, military personnel and academics.