Computer viruses can wreck havoc to the operations of the computer. A computer virus is a type of malware that is intentionally written to gain entry into your computer, without your knowledge or permission. It has the capacity to modify or replicate itself, in which case it will continue spreading. There are varying effects of computer virus. While some simply replicate themselves, others adversely affect the programs and consequently, the system’s performance. This therefore underlines the importance of not assuming that the virus is harmless and leaving it in the system. It is important that you scan your computer for viruses once in a while, so that you can be sure about its protection.
There are various types of computer viruses, classified in terms of techniques, origin, the types of files affected, damage, OS or Platform attacked, as well as the places they hide. Some of the common types include the following:
Resident viruses: These are permanent viruses dwelling in RAM memory. In this case, they would be in a position to overcome, as well as interrupt, all operations that the system executes. Their effects include corrupting programs and files that are closed, opened, renamed or copied.
Overwrite viruses: These viruses delete information that is in the infected files. In this case, the infected files would be rendered totally or partially useless. Unfortunately, you would only clean the infected file by deleting it completely, therefore losing original content.
Direct action viruses: This virus replicates itself, then acts when executed. Subject to satisfaction of particular conditions, the virus infects files located in the folders or computer directory. It is also in directories specified in the AUTOEXEC.BAT PATH. In most cases, it is located in hard drive’s root directory and takes particular action when the computer boots.
File infectors: This virus infects executable files or programs. On running the programs, the virus would be activated, then be able to carry out its damaging effects. Most of the existing viruses are in this category.
Boot viruses: This virus infects the hard disk’s or floppy drive’s boot sector. This would make the computer unable to boot. These viruses can, however, be avoided by ensuring that the floppy disks and hard drive is well protected. Never start the computer using an unknown disk drive or floppy disk.
Directory viruses: This virus alters the paths indicating a file’s location. In this case, when the infected program is executed, you will be running the program unknowingly, since the virus has moved the original program and file to another location. This therefore makes it impossible to locate the moved files.
Macro virus: This virus affects files created using particular programs or applications containing macros. The mini-programs increase their ability to automate some operations, in which case they would be performed as single actions. The user would therefore be saved the trouble of executing them singularly.
There are numerous other types of computer viruses, as they are constantly being created. It is always important that you ensure that the antivirus software is updated so that it can be effective against new computer viruses. Information assurance training provides education on how to stop viruses and other security threats.