What is a computer virus? What is a computer virus:

A computer virus is a computer virus that compiles or inserts into a computer program that destroys computer functionality or destroys data, affects the use of a computer, and is capable of self-replication. Destructive, replicable and contagious.

A computer virus is a set of computer instructions or programs inserted by the compiler into a computer program that destroys computer functions or data, can affect the use of the computer, and can replicate itself.

All garbage that can cause a computer program to be paralyzed is classified as a computer virus.

Programming code that can destroy a computer system.

Computer viruses (computer virus) is a type of data that has the ability to destroy a computer, refers to the compilation or inComputer programsA set of computer instructions or programs that corrupt computer functions or destroy data, affect the use of the computer, and can self-replicate. Computer viruses have five characteristics: infectious, destructive, latent, triggerable, and derivative.

1.Infectivity: Infectivity is the most basic characteristic of a virus, and it is the basis for judging whether a program is a computer virus.

2.Destructive: Occupy system resources, delete or modify files or data, encrypt some data in the disk, format the disk, reduce operational efficiency or interrupt the operation of the system, and even paralyze the entire computer network.

3.Latent: Computer virus programs do not attack immediately after entering the system, and can hide in legitimate files for weeks or even years, infecting other files without being detected, and only activated when the conditions are met.

4.Triggerability: The characteristic of a virus that induces a virus to infect or attack due to the appearance of an event or value.

5.Derivative: Imitated by other malicious vertical attackers, resulting in new computer viruses.

A computer virus is a computer program inserted by the compiler to destroy computer functions or data, and a set of computing instructions or programs that can affect the use of computers and replicate by themselves.

Computer virus (computer virus

Refers to the programming of or in a computer.

A set of computer instructions or programs that corrupt computer functions or destroy data, affect the use of the computer, and can self-replicate.

Origin of Computer Viruses:

Computer viruses are usually generated for several purposes:

1) Pranksters or self-righteous creators.

2) Disgruntled revengers.

3) In order to track the illegal copying of software, the software developer deliberately adds viruses to the software, and as long as others copy it illegally, they will carry the virus.

A computer virus is a self-replicating malicious program that can be destroyed by planting malicious ** in harmful programs and inadvertently infecting other computer systems. The emergence of computer viruses can be attributed to a lack of understanding of the norms governing the use of computers and networks and a lack of attention to security issues.

A computer virus is different from other malicious programs based on its self-replicating, hiding, and spreading characteristics. It can be automatically copied and implanted into the main program or system files, allowing it to be propagated in the computer system. In addition, viruses also show a high degree of stealth, usually by implanting hidden ** or exploiting system vulnerabilities to achieve their own spreading and destruction purposes in a form that is not easy to detect and leaves no traces.

Unlike other software, viruses can threaten the security and stability of the entire computer system, constantly endangering our computing environment.

The types of computer viruses mainly include file viruses, macro viruses, worms, Trojan horses, etc. A file virus is a virus** that is implanted in a common program or system file and continues to infect the user's computer system only when the user runs those programs or files. Macro viruses are viruses implanted in office applications**, and when users open documents, viruses will take advantage of vulnerabilities in applications such as Word to infect and attack computers.

Worms, on the other hand, are viruses that send file-infecting viruses over a network to a remote host. A Trojan horse is a malicious program hidden in seemingly legitimate software, which can steal user privacy, take control of a computer, and even become a larger cyber attack.

The severity of computer viruses lies not only in their ability to infect and damage computer systems and data, but also in the fact that they can spread viruses and cause greater damage to the entire system. Moreover, some more complex viruses can also continuously endanger users' privacy and security by establishing backdoors, stealing information, etc., causing great inconvenience and losses to users. Therefore, it is very important to prevent and combat computer viruses in a timely manner, and we should strengthen our computer security awareness, and equip ourselves with relevant anti-virus software and measures, and regularly carry out system inspection and maintenance to ensure our computer security and avoid the harm of viruses.

A computer virus refers to a set of computer instructions or programs that are compiled or inserted into a computing program that destroys computer functions or destroys data, affects the use of a computer, and is capable of self-replication.

Classification of computer viruses:

1. Boot zone virus: infects the hard disk dominant record.

2. File virus: usually parasitic on the head or tail of the executable file and modifies the first instruction of the program.

3. Mixed virus: It has the characteristics of "guide zone hunger zone" and "file virus".

4. Macro virus: A virus that resides in the macro of a Microsoft Office document or template.

5. Internet virus: illegally enters other people's computer systems through the network, endangering information security.

Prevention of computer viruses:

1. Install effective anti-virus software and set up security according to actual needs.

2. Scan system vulnerabilities and update system patches in a timely manner.

3. Removable storage devices that have not been tested for virus infection should be disinfected with antivirus software before use.

4. Classified management data, all kinds of data, documents and programs should be classified and retained.

5. Try to use the email address with the virus detection function as much as possible, and try not to open unfamiliar suspicious emails.

7. Pay attention to the infection route, attack form and prevention methods of the current epidemic virus, and take precautions.

8. Effectively manage the built-in administrator, guest account and other accounts.

9. Disable the remote function and turn off unwanted services.

10. Modify security-related settings in Internet Explorer.

A computer virus is a group of destructive computer sequences.

A computer virus is a set of computer instructions or programs inserted by the compiler into a computer program that destroys computer functions, or destroys data, affects the normal use of the computer, and is capable of self-replication.

Computer viruses are recognized as the number one enemy of data security, from 1987 computer viruses to the world's general attention, China also discovered computer viruses for the first time in 1989. At present, the new virus is developing in the direction of being more destructive, more secretive, with a higher infection rate and a faster transmission rate. Therefore, it is necessary to study the basic knowledge of computer viruses in depth and strengthen the prevention of computer viruses.

Characteristics of computer viruses

One: Destructive. Destructiveness is the biggest characteristic of computer viruses.

When a computer is invaded by a computer, some important data will be deleted by a computer virus, or a certain function of the computer will not be available. In severe cases, computer viruses can paralyze large areas of computer systems, thus causing huge economic losses to computer users.

Two: Contagious. Another characteristic of computer viruses is their contagiousness.

After a single computer is invaded by a computer virus, it can infect other computers through the LAN or USB flash drive. In particular, through the Internet, it can be spread throughout the entire local area network in a short period of time, or through the public network, it can be spread in large quantities on the Internet.

Three: concealment. Computer viruses are also insidious and are not easy to detect.

For example, some hungry computer viruses pretend to be normal user files or normal user programs, so as to evade the scanning of security software. These disguised viruses will start running when the time is right, and then they will be destructive, and the computer will malfunction inexplicably.

A computer virus refers to a set of computer instructions or programs inserted by the compiler into a computer program that destroys computer functions or destroys data, affects the normal use of the computer, and can replicate itself.

A computer virus is a program that is artificially created, destructive, contagious, and latent in that can destruct computer information or systems. It does not exist independently, but is hidden in other executable programs, and after a virus in the computer, it will affect the speed of the machine at least, and the system will be destroyed by crashing at worst.

Computer viruses can be divided into three types: bootstrap viruses, file viruses and mixed viruses according to the presence of **, and can be classified into three types: source code viruses, embedded viruses and operating system viruses. According to the system classification of computer virus attack, it is divided into viruses attacking DOS system, attacking Windows system viruses, and attacking UNIX system.

Virus Type:

1. Trojan virus.

Trojan horse, also known as Trojan horse, refers to a backdoor program in the computer field, which is encrypted by hackers to steal other users' personal messages and even remotely control each other's electronic devices. Then, the program is executed by disseminating or deceiving the target to achieve the purpose of stealing various data such as passwords.

2. Worms.

The worm lives in one or more computers, it scans other computers for the same worm, and if not, it infects the computer through its built-in means of propagation, so as to paralyze the computer. Usually, the host machine is used as the scanning source, and spam emails and vulnerabilities are used to spread.

3. Macro virus.

A macro virus is a virus that causes the relevant application documents of an application to contain an executable called macro, and an electronic program may allow a user to embed macros in a document. So that a certain operation can be run automatically, and the same operation can also embed the virus into the electronic ** to cause damage to the user's repentance.