Monday, 22 February 2016

Know about Computer VIRUS ? Everything you need to know

Hi readers. In a series of sharing study notes for bank exams, I shared many useful resources for exam preparations. Today I am sharing most important notes that are repeating in almost all the exams. I recommend you to go through all these 7 articles and further download the free question bank and  practice at home. Remember that difficulty level of computer awareness section remain very low, so you need to learn basics only.

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!


But keep learning and sharing knowledge and giving enthusiastic feedbacks!

Article by : Amit Nagpal, Jaipur

3 Ways to Get Rid of Viruses, Spyware and Malware

Viruses, spyware, malware, etc., all have one thing in common: they all suck. They slow down your computer, corrupt your files, illegally steal your info, and more.
You have probably seen those ads online advertising a service that will scan your computer for free and magically cleanyour computer as well as make it 20 times faster. Well, those websites will scan your computer, which is true, however, the majority of them will charge a large fee to get rid of all of the errors found in the scan. In addition, a lot of them are fake and will actually install more malware and spyware onto your computer.
Basically, though, the services use a simple antivirus scanner/remover. There is far better software out there that is available to you for free. By following the tips in this article, you should be able to remove most types of virus, spyware, or malware from your computer.
Obviously, not all malware is created equal and some items are far harder to remove than others. In those types of instances, you best option is to perform a clean install, which is the only sure-fire way to ensure that all remnants of the infection are gone.
virus alert

Method 1 – Scanning

There are thousands of different programs out there in the spyware/virus removal category, many of which are free. The thing to remember is that different virus removal programs will bring different results and none of them are 100% completely accurate.
For example, you can scan your computer with one virus removal program, remove the viruses and then turn around a scan your computer with a different program, which will catch even more viruses that the first program didn’t pick up.
So the best thing to do when you have a nasty infection with multiple viruses, malware or spyware on your system is to run multiple programs. However, a lot of these newer viruses are smart and prevent you from running anti-virus or anti-malware tools inside Windows.
In order to get around this, you have to either scan the system before the operating system boots up or you have to get Windows into Safe Mode and start the scanning process there. To get started, read my post on how to reboot Windows 7/8/10 into Safe Mode.
Once you are in Safe Mode, you need to run several scanning programs one after the other until no more instances of infection are found. So which programs should you choose to run? Luckily, I’ve already written an article on the best free anti-spyware, anti-malware and anti-virus programs currently out there.
In my opinion, you should run SUPERAnti-Spyware first, then MalwareBytes Anti-Malwarefollowed by Spybot and Ad-Adware. Of course, you’ll need an Internet connection for this, so make sure that you enable Safe Mode with Networking.
malwarebytes anti malware
If you have a really smart virus, it will even disable your Internet connection by changing settings in Windows. In that case, read my post on troubleshooting Internet connections and it should fix your problem.
With thorough scanning, most cases of infection can be cleaned completely. It’s a tedious process and requires a bit of technical work, but it usually gets the job done.

Method 2 – Rescue Disks

In addition to the Safe Mode method, you should also scan your computer before Windows even has a chance to boot up. You can do this by using an offline virus scanner or pre-boot scanner.
The way this works is that you will have to use another computer to download an ISO image file from an anti-virus company like Microsoft or Kaspersky and then burn it onto a disc. You will then boot to this disc instead of your normal Windows install and run the anti-virussoftware from there.
Since Windows is not running, the infection can’t interfere and you have a much better chance of being able to remove it. This method is really the only way to get rid of a really nasty virus or malware infection via scanning.
There are a couple of rescue disks that I recommend using. The first one is from Microsoft and is called Windows Defender Offline. Check out my previous article on using Windows Defender Offline to scan your computer.
Again, just like with the scanning software, you should try multiple rescue disks to ensure that the virus or malware has been removed. The other ones I suggest using are:
Kaspersky Rescue Disk
Bitdefender Rescue CD
Avira Rescue System
Note that some of these allow you to download an EXE file and install the files onto a USB stick, which you can then boot up from instead of a CD/DVD. As mentioned, this is a bit more technical, but all the sites have guides on how to create the disks and then use them.

Method 3 – Clean Install

A clean install is not the most fun thing to do, however, it is the one guaranteed way to get rid of viruses, spyware, and malware. It’s pretty straight-forward: when you do a clean install, you delete everything on your hard drive. Therefore, no more viruses.
Some of the time, viruses will not infect items like pictures, text documents, videos, or MP3 files. A good thing to do is to scan all your personal data and if there are no viruses found, copy that to an external drive. In this way, you can perform a clean install and not lose anything important. Obviously, you’ll have to reinstall all your programs, etc., but sometimes you have no other choice.
Performing a clean install is not at all as hard as it may seem, it’s just time consuming because you have to wait for Windows to install. Also, with Windows 8 and Windows 10, the process is even easier because you don’t even need to have your installation CD/DVD anymore.
Check out my previous post on how to restore Windows to factory settings (reinstall Windows). That article covers Windows XP, Windows 7, Windows 8.1 and Windows 10.
clean drive windows 10
If you have trouble using the built-in reset feature in Windows and you don’t have your original Windows disc with you, check out my post on how to legally download Windows and install it on a flash drive.
As long as you have your original product key or in the case of Windows 10, as long as it’s the same computer you had Windows 10 installed on before, you can just boot up from the USB stick and reinstall Windows.
Finally, once your computer is clean and running well again, check out my post on how to protect yourself from viruses and malware in the future. The safest way to keep your computer free of viruses, however, is to create a virtual machine and do everything shady inside of that. If you have any questions, feel free to comment. Enjoy!

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