Computer viruses are instructions or program codes that are inserted into a computer system or computer level to damage data, affect the use of the computer, and are unable to replicate themselves. Computer viruses are different from medical viruses. They do not occur naturally but are created by people using vulnerabilities or vulnerabilities in computer hardware or software to compile instructions and program codes, and then lurk in the computer media through some means. When encountered Certain conditions will be activated and copied by other programs or naturally evolved into certain programs to achieve the purpose of infecting the program and destroying computing resources.
Computer viruses are instructions or program codes that are inserted into a computer system or computer level to damage data, affect the use of the computer, and cannot replicate themselves.
Computer viruses are different from medical viruses. They do not occur naturally but are created by people using vulnerabilities or vulnerabilities in computer hardware or software to compile instructions and program codes, and then lurk in the computer through some means. In the media, when certain conditions are encountered, it will be activated, copied by other programs or naturally evolved into certain programs, thereby achieving the purpose of infecting the program and destroying computing resources.
Characteristics of computer viruses
1. Reproduction
Like biological viruses, they can reproduce. When your program is running, it is replicating itself. Whether Reproducibility is an important factor in determining whether you are infected with the virus.
2. Infectiousness
The virus replicates and then mutates so fast that it is difficult to prevent. Infectiousness is the basic characteristic of the virus. Computers will always spread infected computers to computers that have not been infected through various methods, causing the computers to fail to work. As long as other computers are associated with this computer, they will also be infected with the virus.
3. Latentness
The virus is designed before the attack. It will not be noticed until the scheduled time. When the time comes, it will damage the system. Some even It can be carried on the disk for several years and once the opportunity is ripe, it will reproduce and spread everywhere. When the time comes, some will be marked with special symbols, some will directly destroy the system, some will format the disk, and some will directly delete the disk files.
4. Concealment
Some viruses can lurk in the disk for several years without showing up, and some can be detected. It is very difficult to hide and deal with these viruses when they appear.
5. Triggerability
The virus appears at certain values or times, causing the virus to infect or attack the computer, which is triggerability. Sometimes the virus must lurk in order to hide itself. However, if it lurks for a long time, its lethality may be weakened or even disappear. Therefore, viruses generally hide when they appear. This is the condition that triggers the virus as soon as the computer is running, and the virus will be triggered immediately.
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