Most people simply know that viruses and spyware can both be detrimental to your computer system. What many do not realize is that they are not the same thing. While both are uninvited, disruptive, and potentially destructive, they are two different entities that behave in two different ways. So how can you tell the difference between a virus and spyware?
A virus is defined as a segment of self-replicating code that is planted illegally into a computer program, often to damage or shut down a system or network. It works very much like a biological virus that affects humans. Once a system is infected it spreads the virus like wildfire from file-to-file, computer-to-computer, or network-to-network.
Some viruses are benign and do no actual damage to any part of any system other than replicating themselves to the point that they significantly slow system or network performance. Other viruses are created with malicious intent. They are specifically designed to wreak havoc on any system that comes into contact with them. Ultimately, the damage from certain viruses can be severe and widespread if they are not caught in time. The damaged caused by them can include but are not limited to damaged or deleted files, frequent system or network crashes, or even a reformatted hard drive.
Contrary to popular belief, viruses do not propagate through email alone. While it is true that a good portion of them are spread unknowingly through email messages, there are other ways to contract them. Any type of connection to another computer or file sharing, such as File Transfer Protocol (FTP) or Instant Messaging (IM) can put you at risk.
Spyware is defined as computer software that is installed covertly onto a personal computer to intercept or take partial control over the users interaction with the computer, without the users informed consent. Unlike viruses, spyware is not typically created with malicious intent. In fact, causing any kind of damage to the system would completely defeat its purpose because it needs a host to be able to perform its job. Fortunately, it does not spread like viruses. You can not give another person spyware by swapping files with them or sending them an email.
As the name implies, the intent of spyware is to secretly track and record the users computer usage for the purpose of supplying it to a third party. The type data being sent differences depending on who wants it. If it is for advertising purposes, then your Internet surfing habits are more likely to be the target of interest. If a thief is looking to steal personal information such as credit card numbers or login information, then it will track things like online banking transactions, online purchases, or log in sessions. This is where spyware can be particularly dangerous to the user because they could potentially steal their identity or destroy them financially.
Spyware tends to embed itself deep into the roots of a computer system making it difficult to locate. This in turn can make it difficult to completely remove it from a computer without damaging other programs. It can also slow system performance significantly because it is silently collecting information in the background at the same time the user is working in the foreground. So regardless of whether or not it is meant to be detrimental, spyware can be harmful to your computer as well as your personal information.
While viruses and spyware do have several similarities, they are two different types of malware (malware software). This is important to know because they each require a different solution. Antivirus software does not remove spyware and antispyware software does not remove viruses. You need to know the difference so that you know how to fix the problem. Ultimately, the intelligent thing to do is to run both antivirus and antispyware software at all times. Preventing an infestation now will save you a major headache and possible computer damage later.