Computer Viruses - Non-Technically. Review on Writing Reviews on MouthShut

No! We don't need a doctor here to diagnose the problem. Again, we don't need a hardware engineer to correct the problem. Computer virus has nothing to do with physical damage of your computer. Then what are they and what harm do they cause ? Computer Virus infection is limited basically up to corruption of your files (Movie Files, Word Files, Software files and Operating System Files). It has nothing to do with your computer hardware. So if you feel relaxed now because you don't have any important data in your computer, you can uninstall your Anti-Virus application because your intel processor, hard disc, video card and all will work even if there are infinite number of computer viruses in your computer.

To start in a very simple way let me tell you something about computer programming. Programs are written in many languages like C, C++, Visual Basic, Visual C++, Java and many more. Among all these, C is the most powerful language of all for the very simple reason that it can control devices (hard disc, keyboard, floppy drive etc.) directly. Most of the device drivers like your DirectX, Modem Drivers, LAN card driver, Graphic card drivers and all are written in C.

So now we know that this is the most preferred language for writing fast and efficient programs which can do things quickly. But what if someone writes a program to delete a file or delete ''windows'' folder ? This is a very basic example of a computer virus. Real viruses use the best possible destructive capabilities of a language. A real virus writer takes following things into consideration -

1. The program he writes should be small

   
   




2. It should use less memory ( Dynamic Memory allocation at run time )

   
   




3. It should have a signature that it will put somewhere in the memory to avoid

   
   

reloading itself again and again

1. It should monitor any disk activity so that it can spread wherever you are copying

files ( Hard discs, Floppy, Network drive, LAN )

1. It should be able to attach itself to non-infected files

In olden days when ''C Brain'' virus was launched, software piracy was its conveyance to various computers. But today internet has abridged the gap completely.

The trend started from Marco Virus (basically Visual Basic program embedded in Word or Excel file ) because many people thought that Word and Excel files contained just lines of texts. Even those who knew that programs could be injected in them, did not realise the extent to which these innovative virus writers thought. As the file went from one desk to other and from one office to the other, it infected all the computer files (yes, your word and excel files) which spread the infection further.

Slowly we all become smart, human tendency you see. So we stopped downloading attachments.

''Read the mail but if the sender is anonymous, don't ever download the attachment and you would never have the virus''

This was what many smart programmers suggested to their non-techy friends. But they could never estimate the smartness of Virus Writers. Things jumped from Programming Language to Scripts. Scripts are basically languages which are read by the interpretor program ( CSCRIPT.EXE and WSCRIPT.EXE in windows folder, interpretors in MS-DOS and Windows). Now your Internet Explorer and Outlook Express have Auto-Execute Script option set. I know you must have never thought of that there was something like that. But Virus Writers knew. They used this feature to send HTML files embedded with Visual Basic script or Java script. And unlike previous emails, these emails executed these scripts as soon as you clicked on the emails in the INBOX. Yes! No attachments, all program in the HTML file.

New stuff and as you know ignorance and overconfidence can kill the strongest, it happened again. A complete disaster of important data. Mind you again, no hardware loss. All those hard disks are still running.

This article won't tell you how to safe guard yourself, because your safety is nobody's issue. You have to safeguard yourself. Frequent use of Anti-Virus would reduce the chances of a computer virus getting in.

Myths about a Computer Virus

1. It damages your hard disc or a floppy disc (No!! This can be done only with a

hammer)

1. All viruses can be removed from Hard Disc by Formating the Hard Disc ( No!! you

cannot in case of an MBR virus)

1. Just by reading emails you won't have virus ( you can!! VB Script, Javascript,

IFrames can do wonders which even programmers cannot imagine)

1. Once you start Anti-Virus, you are safe ( Nooooooo! If the Virus started itself

before you launched the Anti-Virus, it might escape detection )

....and many more. So please learn more on net. Save yourself and save others too.

Happy Cleaning...

regards

Tahseen