Computer virus is a self-replicating program which spreads into other data storage programs through duplication i.e. copying itself. Viruses can be compared to biological viruses which are parasitic and destructive in nature. In short, a computer virus can be defined as:
- A malicious program
- Spreads easily
- Destroys all computer equipment it breeds in
- It is important to eliminate the computer virus completely as even a small virus residue hidden in a remote part of the computer device can be harmful
Types of Computer Viruses
The Worm: As its name suggests, this slippery malicious program is known as an email destroyer. It spreads via the email. The worm is very difficult to control and eliminate as it is tough to catch it as it diversifies and spreads from host computer throughout the network.
Trojans: Trojan viruses can be defined as malicious destructive programs which enter and move about the computer under the guise of fake functionality i.e. they give the user the impression of being something else but actually do something else. It is extremely difficult to detect and eradicate Trojans as one can never properly identify them. Trojans can be further divided into:
- Backdoor Trojans: Like the name suggests, Backdoor Trojans enter a computer system without user awareness. They have the potential to destroy normal computer operation and hide within the computer to escape into another one through the network connection.
- Password Stealers: These types of Trojan programs are basically written to invade individual data. In fact, this program is used to decrypt passwords making confidential information extremely vulnerable exposing it to unauthorised personnel.
- D.O.S – Denial of Service: This latest Trojan program is the most harmful blocking Internet sites by sending very large information packages or incorrect requests to various users.
Preventive Measures: Prevention is better than cure. And most users prefer to guard their computer against a virus attack rather than wait for it to happen to summon the data recovery experts. Once a computer is rendered useless and defunct by a virus, only data recovery experts can set it right and retrieve your lost data. They have the technology and the skills to locate the slippery virus and contain it. The next step is to destroy it completely. This is usually done by exposing it to high levels of humidity and heat. Viruses are sensitive to climatic changes and extreme heat and humidity destroy their ability to function and reproduce. But calling data recovery experts after a virus attack is not the norm. Besides being expensive, it is risky. The experts have to be called before the virus can escape to another network-connected computer. In such cases, prevention is a must.
Have anti-virus software installed in your computer and always check it for loopholes and errors. A user has the responsibility to constantly upgrade the antivirus software. This is a tough proposition as virus creators are very knowledgeable and try to write the latest malicious software which cannot be easily eliminated or controlled. As a result, these virus writers always are a step ahead of antivirus software program writers. Common and effective antivirus software programs include Dr Solomon, McAfee, Sophos and Norton/Symantec costing less than 50 pounds. They are also easily accessible through the Internet.
It is best not to run any programs in an infected computer giving the virus chance to spread and destroy more. In addition, users can control virus attacks by not opening and operating any data files in Word or Excel. Computer troubleshooters also often advise against reformatting of the hard drive. In addition rebooting the computer or pressing the ESCAPE key on the computer keyboard is not recommended.
Users should always take data backups on separate data storage devices. This allows them the security of data protection even during a virus attack. But, as argued this is not a preventive step. However, it does beat the very malicious intent of a virus attack of invasion of data privacy.
Famous Virus Attacks: Viruses have been in existence since the advent of the two World Wars. They have paralysed government operations, invaded military secrets and halted functions of industrial giants. The most famous one is the Elk Cloner which first appeared in 1982. It successfully invaded IT giant IBM operations making their technology and market secrets public to the entire IT world. Elk Cloner caused IT panic and led to the invention of powerful anti-virus software. In 1988, the
Computer Forensics (also known as Digital Forensics) specialists can quickly identify whether data loss is due to malicious causes such as virus'.