Virus, Types of Viruses.

Virus :

            “A virus is a “deviant” program, stored on a compute hard drive that can cause unexpected and often undesirable effects as destroying or corrupting data or corrupting window.”  
 

            Viruses can also replicate themselves, and are dangerous because it will quickly use all available memory and bring the system to a halt. Viruses is a very harmful for our computers, laptops, mobiles, Mp3, etc. Virus is that thing which destroys or corrupts the important files to the computers, laptops, etc. An even more dangerous types of viruses is one capable of transmitting itself across networks and by passing security systems.

            

Types of Viruses :

There are many types of viruses some viruses are as follows :

•  Logic Bomb.
•  Time Bomb.
•  (Tape) Worm.
• Trojan Horse.
• Boot-sector-infecting Virus.
•  Multipartite Virus.   

•  Logic Bomb :

            A Trojan horse, which is left with in a computing with the intent of it executing when some condition, occurs. The logic bomb could be triggered by a chance in a file, by a particular input sequence to the program, or at a particular input sequence to the program, or at a particular time or date logic bomb get their name from malicious action that they can take when triggered. 

• Time Bomb :

            A logic bomb is that type of virus which is activated at a certain time or data.

• (Tape) Worm :

A worm is a program that spreads (usually) over network connections. Unlike a virus, it does not attach itself to a host program. In practice, worms are normally not associated with personal computer system. The example of (tape) worm is blaster worm.

• Trojan Horse :

            A Trojan horse is a program intended to perform some convert and, usually, unwanted act which the victim did not expect or want. It differ from a destructive virus in that it doesn’t reproduce through this distinction is by no means universally accepted e.g. Format C.

• Boot-Sector-Inflecting Virus :

            Boot-Sector-Inflecting Virus infect the boot records of hard disk and diskettes and are executed when the system is booted from the hard disk or diskette and installs its own code in the system’s memory so that it can infect other hard disks or diskette later. e.g. Disk killer, Stone virus.