Malware, short for malicious software, is software to help hackers disrupt users computer operation, gather sensitive information, or gain unauthorized access to a computer system. While it is often software, it can also appear in the form of script or code. 'Malware' is a general term used by computer professionals to mean a variety of forms of hostile, intrusive, or annoying software or code. Malware includes computer viruses, worms, trojan horses, spyware, adware, most rootkits, and other malicious programs. In law, malware is sometimes known as a computer contaminant, for instance in the legal codes of several U.S. states, including California and West Virginia. Malware is not the same as defective software, which is software that has a legitimate purpose but contains harmful bugs that were not noticed before release. Sometimes, malware is disguised as genuine software, and may come from an official company website.
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