Malware, short for malicious software, is software designed to infiltrate or damage a computer system without the owner’s informed consent. 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. The release rate of malicious code and other unwanted programs are exceeding that of legitimate software applications, and as much malware are produced today than 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. The best-known types of malware, viruses and worms, are known for the manner in which they spread, rather than any other particular behavior. The term computer virus is used for a program that has infected some executable software and that causes that software, when run, to spread the virus to other executable software. Viruses may also contain a payload that performs other actions, often malicious. A worm, on the other hand, is a program that actively transmits itself over a network to infect other computers. The prevalence of malware as a vehicle for organized Internet crime, along with the general inability of traditional anti-malware protection platforms to protect against the continuous stream of unique and newly produced professional malware, has seen the adoption of a new mindset for individuals and businesses operating on the Internet – the acknowledgment that some sizable percentage of Internet customers will always be infected for some reason or other, and that they need to continue doing business with infected customers. The result is a greater emphasis on back-office systems designed to spot fraudulent activities associated with advanced malware operating on customer’s computers. As malware attacks become more frequent, attention has begun to shift from viruses and spyware protection, to malware protection, and programs have been developed to specifically combat them.