Malware is the generic term that summarizes all types of malicious software. This includes numerous different forms of attackers that can infect a computer system. The damage caused depends on the type of malware. Here we present some of the most important forms of malware:

Computer virus

The computer virus has its name not by chance. The procedure is similar to that of the biological virus. Like a disease infecting a healthy cell, the computer virus crawls into “healthy” systems and causes chaos there.

The code writes itself into a functioning system, so to speak, and then copies itself over and over again. In this way, the computer virus spreads throughout the entire system. Files, documents and images – basically everything you have on your computer – serve as “carriers”.

As with a biological infection, the computer virus can also pass from one carrier to the next. For example, when an infected file is copied from one computer to another. The virus then logically travels with it to the other computer and can spread there as well.


The worm is quite similar to the virus, but computer worms do not require a “carrier” to enter a system. It is possible to transmit worms via files as well, but that is exactly how they can be introduced into a system through a security hole.

Worms usually spread faster than viruses because they do not rely on user action. This means that the user of the computer does not accidentally spread the worm by using already infected files as in the case of the virus. The worm also spreads in the system in this way.

For example, worms can spread independently from e-mail contact to e-mail contact by crawling independently into a security hole. Worms take on a life of their own, so to speak, within the system they infect.


A Trojan is a piece of malicious software that hides inside another program. As soon as this program is installed or used, the Trojan crawls out of its hiding place and nests on the computer.

The actual program may even perform the desired functions. However, the Trojan does its damage in the background. Most often Trojan deletes or moves files and slows down the computer.

You can read more about Trojans in our article.


An “ad” is an advertisement in English and that already describes what adware is all about. It is software that displays annoying advertisements. Usually adware comes in a package with free programs.

When adware is installed, it is often because users do not read the fine print or inattentively always click “Next” when installing programs. In fact, most of the time, the additional adware is pointed out during the installation – even if it is not labeled as adware. Quickly skipping through the installation process then ensures that the program is installed as well. This can often be avoided by sheer patience.


Spyware refers to any form of malware that can be used to collect data or


Malware comes in many forms. The damage varies in size, but in any case it is at least annoying. In the worst case, even serious. Protecting yourself from it is not always easy, but it starts with caution when dealing with unknown files.