Classification and Types of malware

Malicious software (or malware) can be classified in several ways.
Kaspersky Lab classifies all types of malicious software and potentially unwanted objects according to their activity on users’ computers.
The classification system proposed by Kaspersky Lab also underlies the classification of many other antivirus software vendors.
Classification is important for a better understanding of how malware can infect computers and devices, to determine the level of threat they pose, as well as to choose ways to protect against them.
Malware Classification Tree
Kaspersky Lab’s classification system clearly describes each detected object and assigns a specific location in the classification tree shown below. On the “Classification Tree” diagram:
The behaviors that pose the least danger are shown at the bottom of the diagram.
The types of behaviors with maximum danger are displayed at the top of the diagram.