A virus is a malware/harmful software which infect a computer function. Malware = malicious + Software .A computer virus reside on a host computer. A virus attaches itself to a file. A file containing a virus is called infected file.
Damages by Virus
- Modify a file.
- Delete a file.
- Steal user data.
- Record keystroke.
- Stop processing.
- Shutdown PC.
- Damage Hard Disk space.
- Format Hard disk
- Can display false messages.
- Can display advertisement.
- Can use for cyber attack.
A worm is a malware who replicate itself. It fills entire disk with multiple copies of itself.It can spread over network without file attachment.
It is an illegal instruction placed in the middle of a software.The programmer does something useful but the trojan horse does something destructive in the background.It can erase data on your hard disk.leak your information.
Boot Sector Virus:
It destroy the boot record of a hard disk.
It is silent killer.It sit harmlessly in a system and wait for a time or event to activate itself.It can destroy the content of the hard disk.
It transfer from program to program and destroy the infected files.
Macro is the program that execute the repeated commands. When you create a macro, you are recording your mouse clicks and keystrokes.macro virus damages these commands and execute anything destructive.
Activation of Virus
When a virus start working, it is called virus activation.
- By click on an infected file.
- By opening an infected email.
- Some activate on a specific date.
- Antivirus Update.
- Schedule Scanning.
- Scan removable disks.
- Firewall installation.
- Do not open unknown emails.
- Delete Junk emails.
- Avoid pirated software.
- Avoid unnecessary downloading from suspicious websites.
What is antivirus
Anti Virus is a security software against malware in your computing machines. Antivirus is the front line for your computing security but still it can not detect all types of virus and attacks. Attackers are continuously creating new types of malware.