An introduction to the numerous computer viruses
Hardware Threats. That means your PC can be infected by Word Document viruses.
But what are these viruses used for? Spam, Spam, Spam Spammers have also begun using botnets to forward unsolicited bulk email advertisingor spam, through scores of zombie PCs.
On one hand, viruses show us how vulnerable we are -- a properly engineered virus can have a devastating effect, disrupting productivity and doing billions of dollars in damages.
History of computer virus
Brain: considered to be the first computer virus for MS-DOS, it was created by the Pakistani Alvi brothers as an attempt to protect their medical software from copyright infringement — an attempt that quickly got out of hand, much to their chagrin. The Reaper program was created to delete Creeper. Viruses need time to establish a beachhead, so even if they activate they often will wait before doing so. E-mail viruses: An e-mail virus travels as an attachment to e-mail messages, and usually replicates itself by automatically mailing itself to dozens of people in the victim's e-mail address book. They are manufactured, often with great care, intentionally targeting computers, systems and networks. Payload activity might be noticeable e. Once considered a fairly minor problem, spam is rapidly spiralling out of control, and much more than half of all email messages are now thought to consist of unwanted advertising messages. Another way of looking at viruses is to consider them to be programs written to create copies of themselves. It copies itself to the new machine using the security hole, and then starts replicating from there, as well. Multipartite Virus These ultra-versatile viruses double their spreading power by targeting both your files and your boot space. Software development strategies that produce large numbers of "bugs" will generally also produce potential exploitable "holes" or "entrances" for the virus. Basically, they are really contagious. Just get some antivirus. The virus will eventually be activated by the "trigger" which states which event will execute the virus, such as a date, the presence of another program or file, the capacity of the disk exceeding some limit or the user taking a certain action e. Number of Viruses.
In the early days of such malware viruses tended to dominate. A better term would be "search strings ". These viruses modify their code on each infection. How do computer viruses spread?
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