What is Computer VIRUS ? Everything you need
to know
Share on Facebook Share on Twitter Share on
Google+
When I
first read about computer virus, I was surprised to know it is not ‘virus’ –
but VIRUS!
VIRUS is
actually an acronym for Vital
Information Resource Under Siege!
Everyone
says computer technology is changing every day – true – so are viruses changing
and evolving every single day; thus it only makes sense we know a little about
these mischief makers.
To help
with the MCQs, I have italicized and bold-ended the proper terms.
Here we
go:
What is a
VIRUS?
It
is actually a program, created by people who have knowledge to
write software programs. In proper terms, it is called an ‘executable program’,
with bad intentions!
Viruses
are a type of malware, i.e., it is malicious software. You’ll read
about it some more later…
How does
it work? (Or, how does it make out lives difficult!)
A come
attached with another program, and once it is in our system and we execute our
program- we run the virus too!
The virus
replicates itself; that is multiplies when has attached itself to a computer
through an infected program.
So,
suppose we download an mp3 song from some suspicious looking website, and we do
not have anti-virus software on our PC, in such a case a virus may get
downloaded along with the mp3.
Once, the
virus is in our computer, it then starts making copies of itself on our computer.
So, you can imagine, once it replicates, it must need space, thus a virus uses
up the hard disk space and that makes our PC/system slow and makes it hang or
crash!
What other
damages does it do? (-apart from crashing our PC and frustrating us?)
Depending
on what the intention of the person programming the virus was, a virus can do
many different types of damages, like :
(i)
modification of data (Transformers movie anyone?)
(ii) files
maybe overwritten with false information
(iii)
files maybe damaged, so you can not open them anymore or work on them
(iv) it
may even wipe out an entire drive!
(v) it may
make your system to re-boot again and again
(vi) high
threat viruses which target databases of big organizations and MNCs may even
leak top security information of the companies…
A Virus
can be programmed to do anything, so its threat can be anything; it’s a creepy
virtual world out there!
Famous
Viruses?
Yep,
Viruses are sometimes accorded celebrity status too!
(i) First
actual virus – Creeper (1970s), detected on ARPANET.
It
displayed a message on the screen, “I am the creeper, catch me if
you can!”
(ii) First
actual personal computer virus – Elk Cloner (1982), it affected Apple OS
through a floppy and displayed a short poem!
(iii)
First virus to hit Microsoft’s DOS – Brain (1986)
(iv) Most
destructive virus – MYDoom (January 2004)
(v) Most
widespread and fast spreading virus – ILOVEYOU, also known as the love letter!
(2000)
Categories
of Viruses?
Yes,
Viruses are categorized based on what/where/how they affect.
(i)File
Virus/Parasitic Virus: most of the viruses fall in this category. In this type
the viruses come attached to a file, usually a file which is executable, i.e.,
it can be run.
(ii) Boot
sector Virus: these viruses, as the name suggest, affect the boot sector. Which
means it will load before the operating system. It infects through floppy
disks/ hard disks drives.
Imagine, a
virus loading before the operating system does! This can only mean trouble!
(iii)
Macro Viruses: Macro programs consist of a set of commands which executes
itself every time it is run. So, this type of virus affects a
program/application/software’s macros programming feature, to infect documents.
(iv)
Multipartite Viruses: spread and infect in multiple ways, they can effect the
boot sector as well as infect documents/files. They can have multiple means of
transmission and of infection.
6. What
are worms, malware etc.?
(i)
Malware – is the short for malicious software, as the standard definition goes
– is any software which can disrupt normal computer operation, gather sensitive
information or gain access to private system.
It is also
sometimes referred to as badware. Malwares are essentially of two types: (1)
Viruses and (2) Worms.
(ii)
Worms: worms are like viruses in the sense that they do the same damages that
viruses do, they also replicate themselves.
However
the main difference being, it is a standalone malware – i.e., it does not need
to attach itself to any host/executable file. It on its own actively transmits
itself through a network and infects computers.
In other
words for virus infection to happen, a user has to actually run the virus
infected program, only then will the virus program run too. But worms spread by
themselves!
(iii)
Trojan horse: This is my favorite malware as it is named on a very interesting
piece of history which involves Achilles and his heel!
Also known
as the Trojan, it is a malicious software which run without the knowledge of
the user, to gather sensitive information.
Its
specialty is it can run undetected, or when the system is shut down. It can
encrypt/decrypt files and documents and transmit them to those who want it.
Trojan are
disguised in the form of a legitimate and desirable program, that any user
would without suspicion run. User thinks that the program it is running has
nothing wrong with it, whereas the Trojan is secretly doing its work!
Trojan can
also be called a ‘Spyware’; but it is NOT a virus. Why? Simply because Trojans
do not replicate like viruses do!
(iv)
Rootkits: are programs that modify setting in the operating system to keep the
malwares hidden from detection.
How can we
keep viruses away?
By installing
anti-virus softwares!
This is
probably something every one you must have heard or seen or installed one
yourself!
Anti-virus
software protects your system by periodically scanning its
files/documents/programs to check for hidden executable programs.
It works
by searching for those which are a match to any pre-defined virus already
stored in its virus definition file. When there is a match, the anti-virus
tells you that your PC has been infected by ‘so-and-so’ virus, and will proceed
to remove it.
If it
finds that there exists a program which is suspicious, but the anti-virus does
not know its name, then it’ll ask you to take appropriate action.
Every
other day new viruses are programmed and unleashed, and every other day
thousands of e-mails are opened, movies/songs/files/softwares etc. are
downloaded and these viruses find their way into out PCs.
That is
why it is very essential for any PC to have an updated anti-virus all the time!
I hope
this topic was informative and enjoyable!
Next time
you run a virus scan on your PC, take some time and read the descriptions
written alongside the viruses detected; some will be malwares, some worms and
some Trojans!
Beware!
But keep
learning and sharing knowledge and giving enthusiastic feedbacks!
No comments:
Post a Comment