Spyware is a computer program that gathers and reports information about a computer user without the user's knowledge or consent. More broadly, Spyware also includes the program delivering unrequested advertising (Adware), harvesting private information, re-routing page requests to fraudulently claim commercial site referral fees, and installing stealth phone dialers.

Both Spyware and Computer viruses install themselves without the user's knowledge or consent. However, a virus replicates itself but Spyware generally does not self-replicate.

Spyware normally installs itself through one of the following methods:

1. The spyware component comes bundled with an otherwise apparently useful program.
2. The spyware takes advantage of security flaws in Internet Explorer. Internet Explorer can also install spyware on your computer either via a drive-by download. A drive-by download takes advantage of easy installation via an ActiveX .
3. Spyware can also install itself on a computer via a virus or an e-mail trojan program.

Mitigations to prevent the Spyware and Adware

• Log on as a standard user rather than an administrator.
• Keep your operating system regularly updated with patches.
• Modify default Internet Explorer settings to increase security.
• Consider using an alternative browser such as FireFox which is not compatible with ActiveX
• Modifying your hosts files to resolve ad servers to your local host.
• Use a Anti Spyware tool to remove spyware once your computer has already been infected

Anti-Spyware/Adware Technologies

Signature Recognition: Just like in the case of Anti-virus, some software vendors collect Spyware and Adware programs (signatures) and put them into a database. The Anti-Spyware/Adware tool then scan the computer against the Spyware/Adware signature database. If matched, the spyware/adware will be removed or quarantied per user's confirmation. Users of such tools must update the Spyware/Adware signature base frequently for being effective, since there are so many new Spyware/Adware daily.

Behavior based blocking: Some Anti-spyware/Adware tools are capable to block any activities that behave like a Spyware or Adware would do. Such tool may also prompt user to delete or quarantine the Spyware/Adware like programs.

Definitive solutions to spyware issues seem unlikely, because the problems do not lend themselves to a fully rational approach. Also, governments internationally have yet to grasp the importance of spyware and to pass laws to counter its spread. 

Related Terms: Spyware, Adware, Malware, Anti-Spyware, Anti-Adware, Spyware Signature