Type of computer virus

1.Macro viruses

2.Memory resident viruses

3.Overwrite Viruses

4.Direct action viruses

5.Directory virus

6.Web scripting virus

7.Multipartite virus

8.Fat viruses

9.Companion viruses

Most Importaint computer virus

1.                Boot sector viruses

2.                Program viruses

3.                Multipartite viruses

4.                Stealth viruses

5.                Polymorphic viruses

6.                Macro viruses

Type of computer virus

1.  Macro viruses – These viruses infact the files created using some application or programs that contain macros such as doc , pps , xls and mdb . They automatically infact the file with macros and also templates and document that are cantained in the file . They hide in documents shared through e-mail and networks .

2.  Memory resident viruses – The usually fix themselves inside the computer memory. The get activated every time the OS runs and end up infecting other opened files. They hide in RAM.

3.  Overwrite Viruses – These type of viruses delete any information in a file they infect , leaving them partially or completely useless once they are infected . Once in the computer , they replaces all the file content but the file size doesn’t change .

4.  Direct action viruses – These viruses mainly replicate or Take action once they are executed . When a certain condition is met, the viruses will act by infection the files in the directory or the folder specified in the AUTOEXEC.BAT. The viruses are generally found in the hard disk’s root directory, but they keep on changing location. 

5.  Directory virus – Also known as cluster virus or file system virus. They infect the computer’s directory by changing the path indicating file location . They are usually location in the disk but affect the entire directory . 

6.  Multipartite Virus – These type of viruses spread in many different ways  . Their action vary depending on the OS installed and presence of certain files . They tend to hide in the computer’s memory but do not infect the hard disk .

7.  Directory virus -  Also know as cluster virus or file system virus . They infect the computer’s directory by changing the path indicating file location . They are usually located in the disk but affect the entire directory .

8.  Web scripting virus – Most web pages include some complex code in order to create an interactive and interesting contact. Such a code is often exploited to cause certain undesirable action. They mostly originate from the infected web page or browsers.

9.  Multipartite virus – The type of viruses spread in many different ways. Their actions vary depending on the OS installed and presence of certain files. They then to hide in the computer’s memory but do not infect the hard disk.

10.                   Fat viruses – These lardy viruses attack the file allocation table which is the disc part used to store every information about the available space , location of file , unusable space etc.

11.                   Companion viruses – These types of viruses infect file just like the direct action and the resident types . Once inside the computer , they ‘accompany’ other existing files.