Most of them call every malicious software as “virus”. Technically not accurate to call as a virsus for every malicious file or softwares.
Whats is Malware
The “Malware” is a short form of Malicious software. Normally peoples call the common word “virus” to indicate any type of malicious software. But virus is a type of malware only. Some common malware types are listing here.
A virus is a type of malware that copies itself by infecting other files, just as viruses in the real world infect biological cells and use those biological cells to reproduce copies of themselves.
A worm is similar to a virus, but it spreads a different way. Rather than infecting files and relying on human activity to move those files around and run them on different systems, a worm spreads over computer networks on its own accord.
3. TROJAN / TROJAN HORSE
A Trojan horse, or Trojan, is a type of malware that disguises itself as a legitimate file. When you download and run the program, the Trojan horse will run in the background, allowing third-parties to access your computer. Trojans may also be used to open the floodgates and download many other types of malware onto your computer.
Spyware is a type of malicious software that spies on you without your knowledge. It collects a variety of different types of data, depending on the piece of spyware.
Adware often comes along with spyware. It’s any type of software that displays advertising on your computer. Programs that display advertisements inside the program itself aren’t generally classified as malware. The kind of “adware” that’s particularly malicious is the kind that abuses its access to your system to display ads when it shouldn’t.
A keylogger is a type of malware that runs in the background, recording every key stroke you make. These keystrokes can include usernames, passwords, credit card numbers, and other sensitive data. The keylogger then, most likely, uploads these keystrokes to a malicious server, where it can be analyzed and people can pick out the useful passwords and credit card numbers.
A botnet is a large network of computers that are under the botnet creator’s control. Each computer functions as a “bot” because it’s infected with a specific piece of malware.
Once the bot software infects the computer, it will connect to some sort of control server and wait for instructions from the botnet’s creator.
A rootkit is a type of malware designed to burrow deep into your computer, avoiding detection by security programs and users.
Ransomware is a fairly new type of malware. It holds your computer or files hostage and demands a ransom payment. More harmful malware like CryptoLocker literally encrypts your files and demands a payment before you can access them. Such types of malware are dangerous, especially if you don’t have backups.