What is?
Malware, a portmanteau from the words malicious and software, is software designed to infiltrate or damage a computer system without the owner's informed consent. The expression is a general term used by computer professionals to mean a variety of forms of hostile, intrusive, or annoying software or program code. The term "computer virus" is sometimes used as a catch-all phrase to include all types of malware, including true viruses. Software is considered malware based on the perceived intent of the creator rather than any particular features. Malware includes computer viruses, worms, trojan horses, most rootkits, spyware, dishonest adware, crimeware and other malicious and unwanted software. 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, that is, software which has a legitimate purpose but contains harmful bugs. Preliminary results from Symantec published in 2008 suggested that "the release rate of malicious code and other unwanted programs may be exceeding that of legitimate software applications. According to F-Secure, "As much malware [was] produced in 2007 as in the previous 20 years altogether. "Malware's most common pathway from criminals to users is through the Internet: primarily by e-mail and the World Wide Web. Programs have been developed to detect, quarantine, and remove spyware. As there are many examples of adware software that are also spyware or malware, many of these detection programs have been developed to detect, quarantine, and remove adware as well. Among the more prominent of these applications are Ad-Aware, Malwarebytes' Anti-Malware and Spybot - Search & Destroy. These programs are designed specifically for spyware detection and will not detect viruses. Almost all commercial antivirus software currently detect adware and spyware, or offer a separate spyware detection package. The reluctance to add adware and spyware detection to commercial antivirus products was fueled by a fear of lawsuits. Kaspersky, for example, was sued by Zango for blocking the installation of their products. Zango software and components are almost universally detected as adware nowadays.
