Difference between Virus,Worm,Trojan and Spyware?

The most common mistake which peoples do is that they think that Computer Virus, Worm, Malware, Trojan horse and Spyware all are same, so they used them interchangeably. The real scenario in entirely different, these all types of threats are distinct from each other and In this article, I am going to give you a brief overview of what they are? And what is the difference between Virus, Worm, Trojan and Spyware?

Computer Virus:

Computer Virus is a program which attaches itself to another program to infect a computer. Most of the computer viruses attach themselves to executable files, so next time if you see a mp3 file with an extension look like .mp3.exe probably means that the file is infected with a virus. Most of the computer virus becomes active only when a user opens some infected file. As human virus which spreads human to humans, PC virus similarly travels from computer to computer. They can do several high to low priority damages to the computer includes data corruption, file loss, file modification, etc.

It is a good way to install any antivirus program.So, whenever any file is affected with virus, it alerts and remove that virus.

Do You Know?

The first computer virus was "CREEPER" which was an experimental program created by Bob Thomas.however, the first widespread PC virus was “BRAIN” which was created by the two Pakistani brothers Basit Farooq and Amjad Farooq to protect the piracy of the software which they made.

Computer Worm:

Unlike a virus, computer worm does not harm or corrupt any files but still they are much dangerous then virus. They are dangerous because they spread rapidly from one computer to another computer without the knowledge of the user and create unnecessary spaces, files, shortcuts’, etc. In addition to that, they also create unnecessary bandwidth for servers and other networks which can cause them to stop working.

There are many worms attacks have been recorded. Some of the notable attacks were: Melissa (which crash servers by sending users unknown emails causing million of dollars loss), Blaster, I Love You, SQL Slammer(which shut down the internet for a short span of time, In Korea Internet remain disconnected for almost 6 hours).

Difference between Virus and Worm ?

The main difference between virus and worm is that, computer virus only spreads when a user opens some affected file whereas computer worm spreads even without the knowledge of the user. In addition to that, a computer virus can corrupt files, folders, etc. whereas worm does not harm any file instead it creates additional space, files, shortcuts.

Trojan Horse:

The Trojan horse threat is named after a mythological Trojan War b/w Greeks and Troy’s. In that war, some men’s of Greek entered into the Troy city by hiding under the wooden horse (Trojan horse) and thus they attacked troy’s after fooling them. The Trojan horse threat works as same. They are some sort of programs which looks like an original and safe software's but in real these software's has some back doors which are used to bypass the security of the user system.Software creators used that back doors to attack the victim system.

Do you know?

Crack software’s are one of the weapons used for Trojan attack.

Spyware:

Spyware is a type of software which is installed on user computer without his/her knowledge. These types of software’s are used to collect any user information without his/her knowledge. They are mostly used for the purpose of advertisement. Some examples of spyware are Pop Ups Ad, Unnecessary browser extensions, Key loggers, etc. However, some sorts of spyware software also called adware are legal which are mostly use with free trials of software's.

An Illustration of Different Threat Attacks:

After reading this article, I hope now you will have a clear idea about the difference between Virus,Worm,Trojan horses,Spyware.If you have any suggestions/thoughts regarding this article then feel free to mentioned them in comments.

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