This is the latest accepted revision, reviewed on 23 June 2018. Virus writers use social engineering deceptions and exploit detailed knowledge of security vulnerabilities to initially infect systems and to spread the virus. Computer viruses currently cause billions of dollars’ worth of economic damage each year, due to causing system bitcoin mining machine in pakistan lahore, wasting computer resources, corrupting data, increasing maintenance costs, etc. The term “virus” is also commonly, but erroneously, used to refer to other types of malware.
The Creeper virus was first detected on ARPANET, the forerunner of the Internet, in the early 1970s. In 1982, a program called “Elk Cloner” was the first personal computer virus to appear “in the wild”—that is, outside the single computer or lab where it was created. An article that describes “useful virus functionalities” was published by J. Gunn under the title “Use of virus functions to provide a virtual APL interpreter under user control” in 1984. Even home computers were affected by viruses.
The first one to appear on the Commodore Amiga was a boot sector virus called SCA virus, which was detected in November 1987. A viable computer virus must contain a search routine, which locates new files or new disks which are worthwhile targets for infection. Secondly, every computer virus must contain a routine to copy itself into the program which the search routine locates. A virus typically has a search routine, which locates new files or new disks for infection. The “payload” is the actual body or data that perform the actual malicious purpose of the virus. Virus phases is the life cycle of the computer virus, described by using an analogy to biology.
The virus program is idle during this stage. The virus program has managed to access the target user’s computer or software, but during this stage, the virus does not take any action. The virus starts propagating, that is multiplying and replicating itself. The virus places a copy of itself into other programs or into certain system areas on the disk. A dormant virus moves into this phase when it is activated, and will now perform the function for which it was intended. The triggering phase can be caused by a variety of system events, including a count of the number of times that this copy of the virus has made copies of itself.