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a  Malware is a portmanteau, a term combining "malicious" and "software" to describe a type of program designed to steal information from or cause damage to a computer. It includes things like spyware and adware programs, including pop-ups and even tracking cookies, which are used to monitor users' surfing habits without permission. It also includes more sinister hazards, such as key loggers, Trojan horses, worms, and viruses. In simpler terms, it is any software that is intended by the developer to cause harm or exploit people's computers or private records without consent.

The Threat Posed by Malware

The threat posed by malicious software has expanded roughly in parallel with the number of people using the Internet around the world. The earliest well-known examples of malware, which appeared during the early to mid-1990s, were largely the result of experimentation and pranks by curious developers trying to expand their skills. Many of these caused little if any actual harm, and simply resulted in uncommanded actions such as displaying a humorous image on the victim's computer screen. This gradually gave way to efforts to exploit infected computers for annoying but relatively mundane purposes, such as distributing spam email and other forms of advertising.

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