How do computer viruses spread?

Computer viruses are mainly spread in four ways, namely: 1. By using floppy disks infected by the outside world; 2. Infected through hard disks; 3. Spread through optical discs, because optical discs have large capacity and can store massive amounts of data. Execute files; 4. Spread through the network. This method spreads very quickly and can spread throughout the machines on the network in a short time.

The operating environment of this article: Windows 7 system, Dell G3 computer.

How are computer viruses transmitted?

Computer viruses are called viruses because of their contagious nature. The main channels are as follows:

(1) Through floppy disks: By using floppy disks infected by the outside world.

For example, system disks from different sources, software from unknown sources, game disks, etc. are the most common infection routes. Due to the use of virus-containing floppy disks, the machine becomes infected with the virus and is transmitted to uninfected "clean" floppy disks. A large number of floppy disk exchanges, legal or illegal program copies, and the uncontrolled use of various software on the machine have created a hotbed for virus infection and spread.

(2) Through the hard disk: Infection through the hard disk is also an important channel. Because the machine with the virus is moved to other places for use, maintenance, etc., clean floppy disks will be infected and then spread.

(3) Through the CD: Because the CD has a large capacity and stores a large number of executable files, a large number of viruses may hide in the CD. Read-only CDs cannot be written. operation, so the virus on the disc cannot be removed. In the process of producing illegally pirated software for profit, it is impossible to take special responsibility for virus protection, and there will never be truly reliable and feasible technical guarantees to avoid the introduction, infection, epidemic and spread of viruses. Currently, the proliferation of pirated CDs has brought great convenience to the spread of viruses.

(4) Through the network: This infection spreads extremely fast and can spread throughout the machines on the network in a short time.

With the popularity of the Internet, new ways have been added to the spread of viruses. Its development makes viruses likely to become disasters. Viruses spread faster and the anti-virus task becomes more difficult. The Internet brings two different security threats. One threat comes from file downloads. These files that are browsed or downloaded may contain viruses. Another threat comes from email. Most Internet mail systems provide the function of transmitting emails with formatted documents between networks. Therefore, documents or files affected by viruses may flow into the corporate network through gateways and mail servers. The ease and openness of using the Internet make this threat increasingly serious.

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