Adware, Spyware and viruses - What's the difference?
Most of us have heard of Adware, Spyware and Viruses, but how many of us know what they are or what the difference is between them?
In the beginning, there were viruses. Originally they were harmless pieces of code developed in the lab or by programmers working for companies such as IBM and they were basically pranks which professional IT people played on each other. Old IBM hands will remember the "gimme cookie" virus which operated on 360 mainframe machines and which flashed the words "gimme cookie" on attached terminals with increasing frequency. The words would only go away when "cookie" was entered into a terminal. Harmless, even quite amusing during the innocent 1970s era.
The laughter faded quickly when the PC era arrived and shortly afterwards the age of the Internet dawned on the world. Together with vastly increased interconnectivity came the rise of the malicious viruses - software that had no purpose other than to harass and to destroy. The new breed of viruses were conceived by sociopaths and were disseminated worldwide using the amazing reach of the Internet. The Internet made it easy to link up with other people, no matter where they were in the world, and email revolutionized social and business communications, but unfortunately these advances also made it easier for the bad guys to ply their vicious trade.
As defences against viruses grew better and anti-virus software grew more sophisticated, the virus designers had to up their game too, and nowadays the methods of introducing viruses into your PC or laptop are considerably more sneaky than they used to be. Viruses can piggy-back on all sorts of software and media, ranging from email attachments to Word files, from downloaded software to music MP3s. The Internet is now the leading source of infection and anyone who connects to the Internet had better beware that they are not opening the door to the introduction of a malicious and destructive piece of code into their system.
As time went on, the nature of infection changed, as the bad guys realized that there was money to be made from introducing clandestine software into unsuspecting victim's systems. Sure, there's still an abundance of outright destructive viruses around, but they're probably outnumbered these days by the sheer number of Adware and Spyware infections.
Adware really began as legitimate software which was included with downloaded applications or utilities which the PC user sourced from the Internet. In many cases, the user agreed to the installation of the adware on his or her PC (this was normally included in the small print of the user agreement which most people never bother to read). Examples of such applications are music software, CD/DVD copying utilities, instant messaging applications, toolbars and so on.
Adware is often designed to note what internet sites the user visits and to present related advertising to the user. The developers of the application receive revenue from the advertisers for this dissemination of their advertising products. The user may find that the proliferation of adverts and the consequent slowing down of the system to be a nuisance, but in most cases, adware is non-destructive.
Spyware is the malicious cousin of adware. According to Wikipedia's definition, spyware is computer software which is installed surreptitiously on a personal computer to intercept or take partial control over the user's interaction with the computer without the user's informed consent. Spyware can be used to exploit infected computers for commercial gain. Most spyware is installed without the user's knowledge, either by secretly piggy-backing on a desirable application or by tricking the user into installing it (the Trojan horse method).
Activities which spyware facilitates can include monitoring and reporting back on the user's internet activities, delivery of unwanted advertisements, theft of personal information (credit card numbers, banking accounts and passwords etc.) and the rerouting of the user's HTTP requests to advertising or adult sites.
You can see that the threats that the average user faces these days are wide-ranging and sophisticated. Luckily there is a range of equally sophisticated preventive mechanisms that are available to the public. Good anti-virus and anti-spyware programs are to be had and no knowledgeable user should even think of accessing the internet without being equipped by the best protection available.