What is a Computer Virus and How It Transmit | Antivirus Software

Generally, the word virus means "pathogen" and exists in nature. It has a physical effect by infecting humans and animals. And the virus that exists in the computer world is the "computer virus".

However, it is often misunderstood that computer viruses are not a general term for programs that adversely affect PCs and smartphones, but one such malicious program. Originally, the word " malware " is a general term for malicious programs, but in Japan, the word "virus" is pervasive. It's a good idea to recognize that computer viruses refer to specific programs. By the way, malware is a coined word that combines malicious and software.

In this section, we will introduce the basics of computer viruses and infection routes, so please incorporate them as knowledge to strengthen security measures.

What is a Computer Virus?

As mentioned above, computer viruses are a type of malware. Let's organize the types of malware to know their characteristics.

Computer virus

It self-propagates with malware of the type that parasitizes other files, such as software downloaded from the Internet. It is the most common malware and still causes a great deal of damage around the world.

Worm

It is malware that can exist by itself without infecting other files, and it self-proliferates like a computer virus. There is a risk of a pandemic (widespread infection) from computer to computer over the network.

Trojan

One of its characteristics is that Trojan horses appear to be a favorable or non-malicious program. Although it does not self-proliferate, it may be difficult to detect even with anti-malware software.

Spyware

It is malware that hides inside the computer and secretly sends information to the outside. It is a kind of dangerous malware that is likely to be installed without being noticed at all.

Ransomware

It is a type of malware that has become particularly popular in recent years, and when infected with ransomware, important files on the device are locked and a ransom is required to unlock it. In 2017, a ransomware called "WannaCry" caused enormous damage all over the world.

In this way, computer viruses are simple malware when viewed side by side with other malware, but they have the aspect of being scary because they are simple. The simple mechanism is synonymous with the ease of developing new computer viruses, and it is said that 376,639 types of malware are born each day.

Computer Virus Infection Route

Why are so many computers and smartphones infected with computer viruses? Knowing the infection route is the first step in security measures. Here, we will introduce the main infection routes of computer viruses.

Infection using attachments as a medium

Most computer virus infections are carried out by executing email attachments. In many cases, computer viruses are installed in files such as Word and Excel, and files in PDF format. If you download or execute those files, the damage will occur.

Especially recently, as part of a "targeted attack", a clever technique has been used to send spoofed emails that evade the alertness of email recipients and execute attachments infected with computer viruses after sufficient preparation. increasing.

Infected when browsing websites

Unreliable websites can contain malicious programs that can secretly download computer viruses to your computer when you visit them.

Since it is difficult to determine whether a computer virus is embedded by the appearance of a website alone, there are cases where you browse the website without noticing it and become infected without your knowledge.

Infected by inserting a USB memory

Some USB memory sticks have malicious programs embedded in them and infect them with computer viruses when they are inserted into a computer. Alternatively, a file saved on a USB memory may be infected with a computer virus and the infection may spread. Therefore, actions such as inserting an unknown USB memory into a personal computer should be avoided. Keep in mind that some cybercriminals have no purpose, just want to spread malicious intent.

Infected by using file-sharing software

There are also cases of misusing file-sharing software to infect an unspecified number of users with computer viruses. Avoid using unreliable software and use only software with strong security measures.

As mentioned above, computer virus infection routes are diverse and do not always infect via the Internet. Ignore suspicious emails, do not browse unreliable websites, do not use non-owned USB memory sticks, do not use unreliable software, etc., so you can always take measures just by raising security awareness through installing the best antivirus software. Pay the latest attention.