Which malware type is known for replicating itself to spread to other systems?

The malware type known for replicating itself to spread to other systems is a worm. Worms are designed to independently propagate from one computer to another without the need for user intervention or a host file, which is a key feature that differentiates them from other types of malware. They exploit vulnerabilities in operating systems or applications to travel across networks, effectively multiplying and infecting more machines as they continue to spread.

In contrast, a virus requires a host file to attach itself to, and it relies on human action, such as opening a file or running a program, to propagate. Trojans masquerade as legitimate software to deceive users into installing them, while spyware is primarily focused on gathering information from the victim's system without their knowledge. Thus, the self-replicating nature of worms is what distinctly characterizes them in the realm of malware.