*Definition of virus;-
A computer virus is a type of computer program that, when executed, replicates itself by modifying other computer programs and inserting its own code.[ When this replication succeeds, the affected areas are then said to be “infected” with a computer virus.
Virus writers use social engineering deceptions and exploit detailed knowledge of security vulnerabilities to initially infect systems and to spread the virus. The vast majority of viruses target systems running Microsoft windows.It is divided into three types, such as-
1.File virus
2.Boot sector virus
3. Protection table virus
1.File virus;-
A file-infecting virus is a type of malware that infects executable files with the intent to cause permanent damage or make them unusable. … This type of virus can infect a number of operating systems, including Macintosh, Windows and Unix. A file-infecting virus may also be known as a file injector.This virus effect only the file of a system.
Symptom;-
a.Hide or show the application
b.Change the processing speed of an application
Ex;-Rain drop,cascade etc.
2.Boot sector virus;-
A boot sector virus is malware that infects the computer storage sector where startup files are found. … The older types run from the first sector of the storage media that is used to start up the computer. This type was especially common at the time of floppy disks for DOS-based booting.
Symptom;-
a.Hang the system.
b. show the screen in monochromatic/mode
c. Automatically restart the system
d.Does not move the system
e.Change the processing speed of CPU
Ex;-Jo-shy,disk killer etc.
3 Protection table virus;-
Boot sector viruses infect the boot sector or the partition table of a disk. Computer systems are typically infected by these viruses when started with infected floppy disks – the boot attempt does not have to be successful for the virus to infect the computer hard drive.It complete effect the memory system.
Symptom;-
a.show half of the application
b.sometime hide the application
c.change the processing speed of an application
