Computer Virus Q/Ans

What is compute virus?

Computer virus is a computer program that is designed to copy itself and infects or damages a computer without permission or knowledge of a user.

or

Viruses are developed intentionally to damage, infect or even destroy the computer for a designed purpose. A destructive minded person intentionally writes parasitic programs to affect, bother, harm other persons, organization and even nation.

Some of them are: Trojan Horse, Macro Virus, Boot Sector virus etc

Write common characteristics of Computer viruses.

• Viruses slow down the system performance.
• Viruses destroy data and programs from the system.
• Viruses increase the size of executable files.
• Viruses decrease the space on hard disk by duplicating files.
• Viruses cause system to hang or freeze frequently.

Write four symptoms of computer viruses are as follows

• Programs take long time to load.
• Renaming all the files with different names
• Shows unusual error messages on the screen frequently
• Corrupt or deletes system data and programs

How Viruses spread from one computer to another?

• Opening the infected email attachment
• By downloading infected programs from the internet
• By using infected floppy disk, pen drives and CDs
• By transferring an infected program over a network and executing it.

What is Boot Sector Virus?

Boot Sector virus is regarded as one of the most hostile types of virus, a boot sector virus infects the boot record of a hard or a floppy disk. The virus moves the boot sector data to a different part of a disk. This virus allows the actual boot sector data to be read as though a normal start up were occurring.

What is File Infecting Virus?

This type of virus infects program files on a disk. When infected program is launched, the virus code is also launched. After the virus code has been launched, it will normal load and execute the program that has been infected.

What is Multi partite Virus?

This virus is the combination of parasitic and boot sector virus and due to this, it is able to infect both the files or boot sector of a disk. They infect program files and when it is executed, these viruses affect the boot record.

What is Macro Virus?

These viruses infect the Microsoft Office programs such as Excel, Word, Access and PowerPoint. When we open the Microsoft program then the virus is loaded and it affects the normal template or document. Since it is attached in the document, if the infected document is opened on other computer, it affects the computer too.

What is Script Virus?

Script Virus is written in script programming languages, such as VBScript and JavaScript. It can infect a computer through various scripting environments, such as Windows Help, Windows installation files and Windows registry files.

What is Worm?

Worm is a program whose purpose is to duplicate itself. An effective worm will fill entire disk with the copies of itself and it can spread to multiple computer on network essentially clogging the entire system with copies.

Explain Trojan horse Virus. 

Trojan horse is a destructive program that comes as an application. The software initially appears to perform a desirable function for the user prior to installation but steals and harms the system. Unlike viruses and worms, it does not replicate themselves.

HOW TO PROTECT COMPUTER FORM VIRUS?

• We can protect the computer from computer viruses by following ways:
• Scanning the email attachment before executing them.
• Use of a good anti-virus program to scan for viruses.
• Scanning the disk frequently for viruses.
• Not installing the pirated software, especially computer games.

WHAT IS ANTI VIRUS SOFTWARE WRITE 2 EXAMPLE OF IT

Anti-virus software is a computer program designed to detect and remove viruses from the computer system. Any three anti-virus programs are as follows:

• McAfee Antivirus
• Kaspersky Antivirus
• Avira Antivirus