What is the main characteristic of a virus in the context of malware?

In the context of malware, the main characteristic of a virus is that it is designed to cause negative effects on a device. Viruses are a specific type of malicious software that can infect files and programs, causing various forms of harm, such as corrupting or deleting data, slowing down system performance, or compromising the security of a device. The intention behind creating a virus is often to disrupt normal operations, steal sensitive information, or create chaos in a computing environment.

While self-replication is indeed a typical behavior of viruses, what sets them apart is primarily their purpose to inflict harm. This goal distinguishes them from other types of malware, such as spyware, which focuses on data collection, or adware, which emphasizes advertising delivery. Thus, the defining characteristic of a virus centers on its malicious intent to cause damage or disruption.