Consider yourself lucky if you are using a computer running on a Linux operating system, because hardly anybody bothers to create malicious bits of code for it. While users of Macintosh computers are slightly more at risk, computers running on the Windows O/S face the biggest threat from viruses and their ilk. Operating systems and computer technology has moved ahead immensely since the `Brain’ virus, coded by the infamous Sabri brothers of Pakistan. During those days, when the internet had not yet made its presence felt, floppy disks were the only way this particular virus, which corrupted the root sector of hard disk drives, could spread. The threat has increased manifold over the year with hundreds of thousands of virus strains creating havoc to computers that they infect. Antivirus experts categorize most of the under the following categories:
• Spacefiller: These viruses increase the file size of documents, executives, and other files without causing any risk to the files themselves. Due to this, most antivirus software cannot recognize them, as they do not contain typical strings of code that identifies viruses. This virus quickly fills up the empty space of the affected computer’s hard disk drive, causing it to and when booted, and display the BSOD (blue screen of death) on the monitor. This is where antivirus software could have made the difference. As it monitors the HDD in real time, it would have trapped and quarantined the virus the moment it invaded the system.
• Boot Sector: They are extremely dangerous as they infect the MBR (master boot record) of the HDD. The MBR is like the content page of a book and provides information about the location (sector) of programs and data. Once the MBR is corrupted, the operating system will not be able to find the location of the files. These viruses are extremely dangerous and the only way to remove them is by doing a hard format of the HDD. Prevention is always better than cure. One could have avoided this menace by installing one of the reputable AV programs.
• TSR: Terminate and stay resident viruses are deadly and have the ability to alter their code and replicate themselves in various locations of the disk drive. By the time a computer security expert removes one strain, the other strain starts causing chaos. This would not have taken place had there been a proper antivirus program installed on the HDD.
• Direct: Unlike TSR viruses, these malicious bits of code typically attack executive and command files, rendering them useless. They would not have dared attacked these files in the presence of a good antivirus software.
Other types of threats
• Trojans: Like the historical Trojan horse, they remain dormant in the HDD, and attack the system depending on the type of trigger the coder has coded into them. A typical case is a virus that would activate on a specific month and date. This virus created havoc by deleting the data of hundreds of thousands of computers all over the world. Only individuals who had anti trojans installed on their computer escaped this deadly piece of code that bypassed most antivirus software, except a few that had extremely high-security features in them.
• Keyloggers: These critters sit silently on the HDD, noting down each keystroke punched by the user, and transmit the same periodically to the developer. It is easy to understand what that developer could have done, once he had the details of the credit card of the user whose computer was infected by that malware. Excellent antivirus programs have an inbuilt virtual keyboard, which one can use to input private details by clicking the keys on the virtual keyboard with their mouse’s pointer.
• CryptLock: The deadliest variant of virus in the world, which encrypts all the date contained in the HDD, and displays a message providing information where the sufferer should send a sum of cash as ransom, in order to receive a key that decrypts the encrypted data. Only one or two AV programs can allegedly tackle this threat.
Selecting the best AV software
Searching online for the best AV program will not help as all of them claim to be the best. It is better to visit websites operated by professionals who test all AV software available, test each of them on computers infected with different types of viruses, evaluate the performance of each of them using specific parameters, and upload a detailed list of the 10 best AV programs available on the market. http://best10antivirussoftware.com is one of the leading sites where you can find such information.