What is virus:-
The name is enough to scare any user . No computer in the world is protect from virus .Virus infect the computer in many ways and are various types. There are many program to stop them . This chapter will deal with information about virus in details.
Usually when we comes across the term virus we are mistake of the virus we suffer from and get ill with flu and like that . It is actually not.Virus in term of computer is not a living organism which affects our body.A computer virus ,in real , is a tiny program which when enters a computer ,gets associated with pre-install program and application and induces malfunction the program.
The computer virus (a program) when enters the computer destructs the proper working of a computer .it can affect working of a computer ,
⟹ by destroying important information in the computer.
⟹ by making change in the directories
⟹ by formatting floppy and HDD
⟹ by diminishing the speed of the computer processing
⟹ by altering the function of the keys on keyword
⟹ by hindering the booting of a computer
⟹ by altering the size and structure of life
⟹ by stopping or hindering the execution of file
When a virus affected program is executed ,the virus executes itself in the primary memory of the computer.
How virus work:
It is computer program which can duplicate itself. But ,since virus is a computer program it too has its limits ,Virus can do as much as it has been instructed by the programmer through program . for example , a Michael Angelo virus destroys data on march 6 as the programmer has instructed is to ensure ,first,it is 6 march and if he ascertain and if he ascertain that it is 6 march it displace the disk sector.
We also know that no command can be executed themselves .till we issue such as an instruction, Likewise a virus program is either executed directly by the user or when another program is executed by the user .Now the question is why a user will execute a virus on his own computer .for it,virus creator use technique so that the user can be fooled to execute virus .In most of the situation ,virus are present in already .exe file .when file is executed the virus code too are executed.
Usually the virus program gradually start copying themselves in other exe files; and when these file are executed by the user then they start spreading on the entire system.
We also know that no command can be executed themselves .till we issue such as an instruction, Likewise a virus program is either executed directly by the user or when another program is executed by the user .Now the question is why a user will execute a virus on his own computer .for it,virus creator use technique so that the user can be fooled to execute virus .In most of the situation ,virus are present in already .exe file .when file is executed the virus code too are executed.
Usually the virus program gradually start copying themselves in other exe files; and when these file are executed by the user then they start spreading on the entire system.
Reason:-
Using pirated software:-
when user acquire a program illegally it is called a pirated software .A pirated software has max portability to be infected from virus as it comes from unauthentic sources and whenever the pirated software are used,they carry viruses.
Through Network System:-
on the network when gets affected and it is shared with other clients than this cause infection spread among all the shared clits.
Through Secondary Storage Device:-
When a file is copied from a virus affected computer through secondary storage device , virus also gets communicated to that very system.
Through Internet:-
internet is supposed to the most critical carries of viruses.
Types Of Computer Virus:-
Virus can be classified into many categories .They are classified as follow on the basis of their style of affecting the computer system.
Boot sector Virus:-
these type of computer virus get themselves stored in the boot sector or floppy and hard disk .When we boot a computer system it hinders the loading of operating system . if somehow operating system becomes operative , then it start affecting the other device of the computer.
Partition Table Virus:-
these kind of virus affect the partition table of hard disk but do not affect the data in the computer
It only affect MBR -Master Boot Record of the HDD which may have following
- This virus executes itself on the high priority place in MBR.
- It decrease the capacity of RAM.
- it affect the I/O stream of disk which leads to the malfunctioning of I/O program.
File Virus:-
this kind of virus gets associated with exe file . When an EXE file is executed , virus also executed to affect the computer system.
Stealth Virus:-
a Stealth virus is a computer virus that makes every effort to conceal its presence from the user . The techniques range from hiding the increasing the increase in size of an infected file from the user , all the way to infecting the disk in multiple areas so the simply removing the infection from one area does not actually remove the virus.
Polymorphic Virus:-
A polymorphic virus is one that is capable of changing itself so that each infection of the virus is completely different from the original it is very difficult to check such virus since every time they are completely different.
Macro Virus:-
It is type of file such as documents file and spreadsheet file. Micro virus designed as macro ( a special program contain set of command for execution of a particular task in the very software ), can damage data when used
Thanks For Reading .
Mercury
