Malware

Malware is software designed to disrupt, damage, spy on, or gain unauthorized access to computer systems or data.

Computer worm: Malware that self-propagates across networks without needing to attach to another program. Worms spread between systems, often by exploiting network-accessible weaknesses.
Spyware: Software that secretly monitors activity or collects information from a device. Spyware uses covert access to gather data about users or organizations.
Computer security: The practice of protecting computer systems, networks, and data from unauthorized access, disruption, or damage. Malware is one of the threats that computer security aims to prevent and contain.
Morris worm: A 1988 computer worm that spread across the early internet and disrupted many Unix systems. Its rapid spread exposed how a self-propagating program could disrupt networked computers.
Computer virus: Malicious code that replicates by inserting copies of itself into other files or programs. A virus is one specific kind of malware, not a synonym for all malicious software.
Trojan horse (computing): Malware disguised as legitimate or desirable software to persuade people to install or run it. A Trojan relies on deception rather than self-replication to gain a foothold.
Keylogger: Software or hardware that records keystrokes, often to capture passwords and other sensitive information. Keyloggers are a focused form of surveillance for collecting typed information.
Computer vulnerability: A weakness in software, hardware, or system configuration that can be exploited to compromise security. Vulnerabilities give malware an opening to compromise systems.
ILOVEYOU: A 2000 computer worm that spread through email attachments and affected systems worldwide. The outbreak demonstrated how social engineering could amplify malware distribution.
Potentially unwanted program: Software that may be intrusive or undesirable but is not necessarily malicious by design. Unwanted behavior alone does not make a program malware.

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