Types of viruses

File viruses represent the classic form of computer virus. They infect specific files, such as executable programs, and replicate when these program files are called.

“Trojan horses” or “Trojans” are used to infiltrate other malicious programs onto your computer, e.g., to

• spy out data and passwords,
• to open your system unnoticed for access from the outside,
• use your computer for attacks on other systems, or
• encrypt your data and then blackmail you.

The virus type “worm” is an independent, self-replicating program that prefers to spread in networks and try to disrupt their work.

Bots (as an abbreviation for “robots”) are computer programs that work independently and are active without the intervention of users*. This is problematic when they act in secret. A bot “hidden” in the PC will carry out attacks on websites or “steal” data from your computer.

A hoax is not a virus, but a kind of “bad joke”, often in chain letter format. You are prompted by a text message to forward it to others. This unleashes the intended effect of a virus, namely mass distribution. Today, chain letters are mainly found in social media.