How Viruses Contaminate Your Computer
Viruses are little bits of software that normally have a
negative impact on our computers when they are activated.
Usually viruses are attached onto other software programs
(games, disk utilities, office documents/Macros, screen-savers),
and are activated when these normally harmless programs are
started.
A virus is inactive until the infected program is run or an
infected boot record on a floppy/CD is read. When the virus is
activated it loads into your computer's memory where it can
perform its nasty job or spread itself to other programs on your
system or computers in your network.
Floppy disks used in an infected system (or CD-Roms/DVDs burned
on an infected system) can then carry the virus to another
machine. Programs downloaded from USENET, or file-sharing
programs (Kazaa, Morpheus, Limewire etc.) can also spread a
virus. More frequently now, email is also becoming a favourite
way to spread viruses, Trojan horses and especially internet
worms.
It should be made clear, that USENET and file-sharing programs
do not create viruses or infected files in any way. It is
certain anti-social people who create viruses, and then use
these services to spread the infected files to other users on
the system.
This is very similar to cars and highways in that Ford, Toyota
or the highway makers do not cause traffic accidents, it is the
idiot who got drunk and then drove who causes a 14 car pileup.
Of course if there weren't cars or highways there wouldn't be an
accident... then again, the idiot would still be getting smashed
and driving his horse-carriage into the store window.
When you get a virus on your computer, it can erase everything
that you have on your hard drive. Each virus is different - some
of them come up as strange messages on your screen, while others
just work at eroding the files on the computer. A virus just
doesn't appear in your computer - you have to put them there,
usually by running program from the Internet that contain
viruses. They sometimes come from attachments in emails. It is
possible that an email from a friend could contain a virus if
that person's computer is infected. With anti-virus software
installed on your computer, this will tell you whether or not it
is safe to open the email with a message such as "No virus
detected in incoming mail:
When you do get a virus through programs or mail, it hides in
your computer and when you save data in the computer, you also
save the virus. Then it starts to infect all the other files in
your computer. When you send files to a friend or co-worker, you
also send the virus to his/her computer. After a while the virus
starts to crowd the data in your files and causes major problems
with the system, such that you may not even be able to open
important documents or you may not be able to open any of the
programs on the computer. The virus won't affect the memory of
your computer, but it will affect any disks that you use to save
your work.