Computer Security

1. File Infectors : This Type of virus infects programs or executable files (with an .exe or .com) extension. When one of these programs is run directly or indirectly, the virus is activated producing damaging effects. Majority of viruses belong to this category,and can be classified depending upon, the actions they carried out.

2. Boot Virus : Boot-sector viruses are spread to computer systems by booting, or attempting to boot from an infected floppy disk or Hard disk. This type of virus infects the first sector i.e, Boot sector of a floppy disk or master boot record in hard disk. A boot virus ,may make it impossible to start the computer.

3. Macro Virus : A Micro virus is a computer virus, that infects a Microsoft word or excel or similar applications,and causes sequence of actions performed automatically. When the application is started micro virus is often spread,as e-mail virus and written in macro language i.e a language built into a software application such as a word processor.

4. Network Virus : Network Viruses spread through (LAN) i.e Local Area Network,and sometimes throughout the internet. Genrally network viruses multiply through shared resources i.e shared drives and folder.

5. Program virus : A program virus becomes active when the program file (usually with extensions .BIN, .COM, .EXE, .OVL, .DRV) carrying the virus is opened. Once active, the virus will make copies of itself and will infect other programs on the computer.