Spy programs present a serious danger to the security of individual and networked computer systems.

One of the most dangerous features of all spy software is the registration of keystrokes made by the user, with the purpose of monitoring computer activity. When the user types a password and his credit cards details on the keyboard, at this moment his every keystroke might be recorded. Besides, modern spy software allows capturing the text from application windows. In other words, the spy software can intercept the text from the document even if the user does not type it on the keyboard, but just opens and views the file.

For spotting and disabling spy software, which can be installed without the knowledge of a PC user, programs of various types are now used providing more or less effective protection exclusively against the KNOWN spy programs with the help of signature analysis. For effective operation of such programs it is necessary to receive a sample of the spy software, to pick out its signature and to include it into the base. After the signature base updating the users of personal computers get a possibility to struggle with this kind of spy software. This is the main principle on which many known companies - manufacturers of the anti-virus and anti-trojan software work.

Antivirus product responds to the penetration of a virus with a keylogging module inside when the information capturing has already taken place, since new information had not been added to the virus base yet and correspondingly had not been updated at the user's computer.

Personal Firewall asks many questions and even experienced user can answer them incorrectly thus ill-configuring it. For example, some commercial monitoring programs use processes of program products with knowingly permitted access to the Internet (browsers, mail clients, etc.) Usually the user must permit them accessing the Internet. And as the result: the information is stolen, because the anti-virus program failed to perform its functions properly, and it will be sent unnoticed to the Internet to the address, preliminary specified by the hacker (or some other person).

Anti-keylogger is the product that works silently, asking the user no needless questions and performs its task constantly in the background.