Malware or malicious software could be defined as the software that cyber criminals develop with malicious intents- like accessing and causing damage to a computer/mobile device or a network of computers, mostly without the user(s) being aware of the infiltration done by the malicious software. A computer virus is a malicious software that can copy itself onto multiple computers, in the process performing additional malicious tasks like corrupting data or destroying data. Trojan Horse is the kind of malware that disguises itself as a legitimate tool that would trick a user into installing it so that the hacker can use it to carry out malicious activities.”]
Source: https://hackercombat.com/a-brief-history-and-the-different-kinds-of-malware/