What Is Computer Virus And How To Prevent It

 Are you interested to know what is Computer Virus?  Everyone knows how to use the computer and people who uses the computer must have heard the name of the virus.

 Virus, this name is a very familiar name in the world of Internet. Along with this, it is also a very scary name because it is very harmful for your computer and other electronic gadgets.  That is, if it enters the system once, then it can also spoil it and can also destroy your data.

 Just like Virus is not good for our health and they spread many diseases in our body, in the same way these Virus also cause many damage in the computer system. Therefore, it is good for all computer users to keep information about them.

 Computer Virus, Many people will know something about this and what it is and what it does. But there are also many people who may have heard the name of the virus but they will not know what the virus can do in your computer.

 So today I am going to tell you in this article about what is a virus and how to kill computer virus.  Hopefully you will get to know a lot by reading this article.

 What Is Computer Virus In Computer:-

 Computer Virus is a small software program that is designed to delete your computer's operation and computer's data or access it.

 Without our knowledge, computer virus can spoil the system in such a way that it is not just for us to fix it.  The computer runs from many software programs, without any program the computer cannot work.

 Software programs are made to make the computer work properly and some programs are also made to spoil the work of the computer.

 The computer was invented by humans, its program was made by humans itself to run the computer and as I said the virus is also a small program, it has also been made human.  Computer virus is not natural, they are not made by themselves, programmers also make it consciously so that they can spoil other computers.

 Or we can also say that Virus are actually computer programs that are destructive rather than productive. Its basic purpose is to deliver damage to the place of providing help.

 History of Computer Virus:-

 Robert Thomas, he was the first engineer who first developed a computer virus while working at BBN Technologies in 1971.

 This first virus was named "Creeper" virus, and it was an experimental program that Thomas himself had done to infect the mainframes of ARPANET.  After infecting the Virus system, it displayed on the following message screen, "Increased the creeper: Catch me if you can".

 The original wild computer virus that was first tracked was "Elk Cloner". This Elk Cloner had previously infected Apple II operating systems through floppy disks.  Richard Skrenta developed this virus in 1982, which was a teenager at that time.

 Suppose computer viruses were designed according to prank, but it seems that if a malicious program is installed in the memory of the computer then it can do many such things by running the system to the user. You can also stop further and they will not have any control over these malicious programs.

 The first person to name these Malicious Programs as "Computer Virus" was Fred Cohen, who named it in 1983.  This name came to the fore when he named these programs in an academic paper titled "Computer Viruses - Theory and Experiments" where he wrote full information about these malicious programs such as how it works, what  it  Can do etc.

 What Can Computer Viruses do:-

 Computer virus can corrupt or delete the data in the computer.  You can completely eliminate the data stored in your hard disk. Computer virus also spoils their computers by going to other computers through e-mail attachments.

 Virus slows down the speed of your computer. It destroys your files and program.

What Is Malware In Computer:-

 Malware's full name is malicious software.  It is also a software program that gives access to computers. Malicious software means bad software which is not good at all and once it comes in your system, it can completely spoil your system.

 Malware is also the name of a virus which starts to slowly erase the data of your system.

Where do Malware come from in our computer?  

Malware can come from many places in our system and the most used source which is common source today is internet.

 On the Internet, we get some information every day.  If we went to any malicious site to get the same information or downloaded pirated software, games and movies from somewhere, then malware online comes into our computer from there.

 This was about how online malware gets into our computer, now we will know how offline malware gets into our computer.

 We all use Pendrive, CDs, DVDs in our computers. When we bring Pendrive and CDs from another place to connect to our computer to collect data then malware comes into our computer from all these things and our computer  destroy data.

 Types of Malware:-

 Malware is of three types - Virus, Worms and Trojan horse.  These three are different, their work is also different.  These three spoil your computer in different ways.  Let us know about these three and what they do.

What Is a Virus:-

 Virus can corrupt the files and software in your computer.  Suppose there is a word document in your system in which the virus has come, then it will delete the data of your document or corrupt the document from which you will not get any information from it.

 Or it could also be that this virus can completely corrupt your word processing software.  In such a situation, if you copy or share a corrupted file, then this virus goes to another computer and also spoils its system.

Types Of Virus:-

 Computer virus is a type of malware that if entered into the computer's memory, then it can multiply itself automatically and can also change programs, applications.

 Here computer infects occur when these malicious codes keep replicating themselves.  Here I am going to provide information to you about the types of these computer viruses.

Boot sector virus:-

 This type of virus infects the master boot record and removing them is a very difficult task and often the system has to be formatted to remove them.  These are mainly spread by removable media.

Direct action virus:-

 They are also called non-resident virus, once it is installed, it stays hidden in the computer memory.  It stays attached with the specific type of files that it infects.  They do not infect user experience and system’s performance.

Resident virus:-

 Like direct action viruses, resident viruses are also installed in the computer.  Apart from this, identifying them is also a smile.

Multipartite virus:-

 This type of virus can affect the system in multiple ways.  These infect both the boot sector and executable files simultaneously.

Polymorphic virus:-

 Identifying these types of viruses is a very funny thing for a traditional anti-virus program, as these viruses change their signature pattern frequently whenever they replicate themselves.

Overwrite virus:-

 This type of virus deletes all the files that they infect.  To remove these viruses from the system, the user has to delete all the infected files, causing data loss.

 It is a very happy thing to recognize these viruses as they are spread through emails.

 Spacefiller Virus - Also called "Cavity Viruses".  They have been given this name because it fills all the spaces in the code, so it does not harm the files.

File infectors Virus:-

 Some file infector viruses attach to program files, such as .com or .exe files.  Some file infector viruses also infect files with .sys, .ovl, .prg, and .mnu.

 In the same way when a particular program is also loaded, the virus also gets loaded automatically.  These viruses come in the users' computer with email.

Macro viruses:-

 As suggested in the name, these macro viruses mainly target macro language commands only in some applications like Microsoft Word.

 These macro viruses have been designed in such a way that it easily adds its malicious code to genuine macro sequences.

Overwrite Viruses:-

 This virus has been designed in such a way that it can overwrite itself and destroy any file or application data.  It starts to overwrite its own code once it starts an attack.

Polymorphic Viruses:-

 This type of virus is used more often by cybercriminals.  This is a type of malware type that can easily change or mutate its underlying code and without changing any basic functions or features.

 This does not make it vulnerable to which anti-malware.  Whenever an anti-malware detects it, it modifies itself which makes it very smiling to get hold of it.

Resident Viruses:-

 This virus implants itself in the computer's memory.  Basically, there is no need of original virus program for infection to infect any files or program.  Even if we delete the original virus, a version of it is stored in memory, which itself activates itself.

 This happens when computer OSs load some applications or functions.  Since it is hidden in the system's RAM, it is often not able to detect any antivirus or antimalware.

Rootkit Viruses:-

 This rootkit virus is a type of malware type that secretly installs an illegal rootkit in the infected system.  With this, it opens a door for the attackers which gives them full control over the system.

 This allows the attacker to fundamentally modify or disable a program or function.  These rootkit virus can bypass antivirus software very easily.  Rootkit scanner is required to capture them.

System or Boot-record Infectors Viruses:-

 These boot-record infectors infect executable code that is found in specific system areas of the disk.  As the name suggests, they infect more in USB thumb drives and DOS boot sector.

 These boot viruses are not seen much these days because the present system does not depend on much physical storage media.

What is Worm:-

 Worms are also like viruses, but they multiply themselves and try to spread themselves as much as possible.  Which means that if there are worms in your system, then they start making many copies of different files, due to which the system slows down.

 If we copy and share the same files with another computer, then worms will go there and slow down that computer by making many copies of files.

What is Trojan Horse:-

 Trojan Horse is a very dangerous malware.  These malware come by hiding your identity in your computer.

 For example, if you are using the internet and you have visited a site, you are shown an add such as "click here to win smartphone" and if you click on it, then trojan horse malware comes into your computer only through it.  Will go and you will not even know about it and your system will completely ruin it.

 They are also present on the internet in the form of a lot of software, you will think that it is a genuine software, but in reality it remains a trojan which is hidden inside that software and once they come in your computer, then it will be in your computer.  Start slowing down.  With that, he would open a door so that different kinds of viruses and worms get into your computer.

Signs of Virus Infection In Computer:-

 How to know if your system is infected with Virus or not.  Therefore, here I am going to tell you about some warning signs, which is very important to know for all computer users -

i) Slower system performance

ii) Frequent pop-ups in the screen

iii) Own programs

iv) Files automatically multiplying / duplicating

v) New files and programs are automatically installed in the computer

vi) Files, folders or programs are automatically deleted and corrupted

vii) Weird sound from hard drive

 If you see such warnings in your system then you should know that your system can be infected by virus.  So, as soon as possible download a good antivirus software and scan it.

How To Protect Your computer from Virus Attack:-

 Here I am going to give you some tips that will make it easier for you to avoid these viruses.

 What Should Be Done:-

 1. Always install a good Antivirus in your system and keep updating it from time to time.

 2. If you do not have any information about his sender, then you should not open it.

 3. Do not download anything from Unauthorized Websites such as MP3, Movies, Software etc.

 4. Get all downloaded things scanned well.  Because they are more likely to have a virus.

 5. Use removable media such as pendrive, only after scanning the disks.

 6. If you visit any website, then you should take care of one thing that it is a popular and registered website and do not click on any such link which will cause you trouble later.

What Should Not To Be Done:-

 1. Never open any email attachment that you do not know about that sender.

 2. Do not try to open any unsolicited executable files, documents, spreadsheets, without scanning.

 3. Do not download documents or executable software from untrusted websites.

 4. Ads that give you greed, click here and win the lottery, then never click on such pairs.  We get similar greed in our e-mails too, so you should never open that mail as there are more chances of malware in it.