SafeguardĀ Your pc and What are virus ? Firewall can stop?
As a computer user, you face a major challenge in keeping your computer free from destructive viruses.A virus is a program or piece of code that is loaded onto your computer without your knowledge and runs against your wishes. Most viruses can also replicate themselves, which is dangerous because they can quickly use all available memory and bring the system to a halt. Some viruses are capable of transmitting themselves across networks and bypassing security systems.
In 1987 a virus infected ARPANET, a large network used by the Defense Department and many universities. As a result, a number of antivirus programs became available to the public. We can distinguish between general viruses, worms, and Trojan Horses:Viruses are designed to spread from file to file on a single computer. A worm is a special type of virus that can replicate itself and use memory, but cannot attach itself to other programs. It is designed to copy itself from one computer to another over a network.
A Trojan Horse virus contains a hidden surprise intended by the programmer but totally unexpected by the user. Trojan Horses are often designed to cause damage or do something malicious to a system, but are disguised as something useful. Unlike viruses, Trojan Horses don’t make copies of themselves. Like viruses, they can cause significant damage to a computer.A virus hoax is a message sent via e-mail intended to scare people about a non-existent virus threat. Users often forward these alerts thinking they are doing a service to their friends, but merely waste other people’s time and effort. The increased email traffic can soon become a problem in Internet access systems. Most viruses enter your computer system through an attachment to an email. Contrary to what is widely believed, the attached files can infect your computer even if they aren’t opened. Some new viruses can attack your system even if you merely open an email. Your computer can be infected even if the email attachment is merely resident on your hard drive but has not been activated.So it’s best not to open any suspicious email messages and avoid opening ANY attachments if possible. If the file is important to you, have the person transmit the information in some other form. For example, instead of sending a .doc document by attachment, have them create an HTML document to link to the .doc file (your browser can open the .doc file in Word).
Viruses can appear in many guises, the most common being:
Guidelines for keeping your Computer free from Viruses
Watch for information on virus infection vulnerabilities of specific software. For example, in the update below, Internet Explorer and Microsoft Office 2000 have now been admitted to have virus vulnerabilities which require a patch. Download the patch and load it into your computer as soon as possible.