Computer viruses and worms are detrimental programs that break into computer files from outside through certain channels. The computer virus spreads infection through files, whereas the worm propagates itself by self-replication. Generally, the worm is considered one type of computer virus.
Routes of infection are through attached files, downloaded files from websites, external storage media, etc. These days, a new type of virus has emerged which infects files when certain websites are merely visited, so a digital environment without antivirus software is quite dangerous.
Symptoms are quite diverse. Major symptoms are boot-up failure, frequent freeze, irregular display, deletion of saved files and data, random distribution of saved files and data, system breakdown and so on. Some viruses automatically attach infected files to e-mails and send them to addresses on the infected computer. That is, infected computers and their users, although they are victims, could inflict damage on other computers and their users at the same time.
More aggressive viruses leak the contents of computers to a third party or manipulate them through the network. In some cases, an infected computer itself becomes available on the Internet so that anyone can visit it. It happens frequently these days that users’ own documents and reports, digital photos and other saved computer files flow out onto the Internet.
First of all, install antivirus software. After installation, keep the software up-to-date, or you will be affected by the new types of viruses that are emerging day by day.
Other helpful measures are:
The following cases are examples of Good or Bad practice:
→Opening attached files could cause infection. You must not open attached files from strangers indiscriminately.
→It triggers further spread of infection. You should report promptly to a staff member or an assistant.
Here are some examples concerning computer viruses.
Most viruses spread infection through attachments to e-mails. “Happy 99”, a once rampant virus, spread by attaching the program with the same name to e-mail. When the receiver runs the program, a picture of fireworks is displayed on the screen. While the receiver enjoys watching them, the virus breaks into the computer system. Then, it sends e-mails to addresses in the address register with attached files of “Happy 99” automatically. This is how the virus spreads infection.
Another program called “TROJ_NETBUS,TROJ_BKDOOR-G”, as well as Happy 99, is a malicious virus that allows a third party to remotely control the computer system or secretly check data entry, once the receiver executes the file.
Recently, many users have fallen victim to “Antinny”, an extremely malicious virus (the same type as worm, malware and Trojan horse) that was disseminated through the file exchange software “Winny”. Just as Winny had serious consequences by encouraging illegal file exchanges, the leakage of personal information promoted by Antinny has become a big problem. It caused considerable public concern that some company employees, government officials and workers of organizations had used Winny to obtain customer information surreptitiously.
Even if you don’t use Winny yourself, just opening files sent from Winny users or distributed on the Net by Winny users could cause damage to your system.
Once information comes out onto the Net, it is highly probable that it continues to be copied easily and endlessly, making it almost impossible to retrieve or exterminate the data. Instead of treating the problem as other people’s concerns, please be aware of the risks and take appropriate measures.
“Bubble boy” is a type of virus that infects the computer system if the user reads an e-mail message in html files. Before Bubble boy, there was no virus that infected the system just by the user reading messages. These days, this type of virus is sweeping across the Internet. Users must pay special attention, particularly to e-mail with attached files from strangers. If you receive e-mail infected with the virus, don’t open the attached files; just delete them.
Recently, a lot of viruses have appeared which infect the system just by the user visiting a certain website. As long as there exists viruses that sneak into computers before users are aware of them, installing antivirus software is essential.
If you execute a file infected with a virus while using computers in Information Science classrooms, Study Halls, the Vocational Guidance and Career-Building Support Office, etc. on each campus, report it to the staff immediately.
You may receive “chain e-mail” that gives false information about a certain type of virus. With the Internet in widespread use, misinformation also spreads more quickly and widely. If you are not certain about the authenticity of the information, you should take appropriate measures to protect your computer, instead of creating a ruckus, and await information from a credible company or organization. In any case, don’t forward chain e-mail.