A computer virus is a computer program that can copy itself and infect a computer. The term "virus" is also commonly but erroneously used to refer to other types of malware, including but not limited to adware and spyware programs that do not have the reproductive ability. A true virus can spread from one computer to another (in some form of executable code) when its host is taken to the target computer; for instance because a user sent it over a network or the Internet, or carried it on a removable medium such as a floppy disc, CD, DVD, or USB drive.Viruses can increase their chances of spreading to other computers by infecting files. Viruses are sometimes confused with worms and Trojan horses, which are technically different.Some viruses and other malware have symptoms noticeable to the computer user, but many are surreptitious or simply do nothing to call attention to themselves.
Prevention Strategies:
Anti-virus software and other preventive measures : Anti virus is a protective software designed to defend your computer against malicious software. in order to be an effective defense, the anti virus software needs to run in background at all times and should be kept updated so that it can detect the unwanted threats.
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