Spyware definition 

Spyware is a kind of program that works in invisible mode and spies every action of user without his knowledge or permission. Spyware connect to the Internet in a background or using backchannels. Every program that doesn't perform it's basic functions and works in a background can be called spyware. It installed together with freeware. it is purpose is to obtain as possible more information about user and to send it to home server. There are third parties involved, who used this information.

Spyware is often use for commercial purpose. It can become e-marketing tool for observation of Internet users and particular site's visitors. Obtained information is used for advertising and site's promotion. Companies are able to purpose some specific services and advertisements for particular user according to his habits.

Sometimes you can find spyware called as Trojan-ware or Trojan for advertising. It's because spyware comes to computer bundled with other programs, most times with freeware. User downloads some freeware and along with it he gets spyware. Malware, trackware, hijackware, scumware, snoopware, thieftware are also considered as spyware which breaks in using freeware.

After you had spyware installed into your system, you will get a lot of annoying pop-up advertisements. Even you don't have IE running at a time, pop-ups may appear. Your every action will be tracked in case to get all information about your online and offline habits. every personal information that you enter to PC, will be logged by spyware. It may cause carding or identity theft and this is very serious. Spyware can make security holes and inform third parties that you have dial-up connection. This may bring dialer to your PC, which will bring fantastic bills for phone services. But beside all that, spyware like any other other software will use your computer system resources, what will cause slower work of your PC. It may also change web browser's setting, change homepage and that is very insecure and annoying.

Most of spyware come to your PC bundled with freeware, free music and video. It also brings some adware. If you use cracks or cracked programs you can get some spyware too. Cracker may try to get data for carding. Plugins and toolbars for IE are often bundled with spyware and adware. Spyware is available in sites of adult content, cracker's sites and sites that offer freeware. Often advertisement on web sites contain spyware and adware. Adware is a program for advertising. Freeware are full of adware. It's because some companies using adware advertise themselves and profit of this goes to freeware maker and for the company. But don't think that adware is harmless software. Adware just like spyware collects information about you and your habits for advertising and web sites' promotion.

Any program, macros or script can be considered as adware if it opens unwanted windows with advertisements. Same of adware are very malicious. They can work as nukers. Malicious adware can install and reinstall itself, damage computer system and much more. Users don't have opportunity to remove it, so the best solution is anti-spyware software.

Spying can be either controlled by third parties cookies or by particular program. Those spywares that you can get with freeware can be categorised into:
Internet spyware;
HDD spyware;
Keyloggers;
WWW-spyware.
Internet spyware is program for information accumulating. Information contains data about Internet connection, it's quality, etc. HDD spyware is used to gather information from hard disk. Keuloggers are programs that log every keystroke of your keyboard. And WWW-spyware is for Internet users' habits spying.

Third party cookies are less dangerous for your privacy. They collect only aggregate information. Obtained information includes IP address, visited sites and how many times user has visited some page. But even cookies can be malicious when there is collected much more information by third parties that it should be and user isn't informed about it. Most of these cookies are known for anti-spyware databases and they are removed.

Spyware is used for e-marketing. Obtained data is stored in huge databases and analysed. After analysis advertisers and managers can offer certain ads and services for each user. It may seem good for users, but sometimes all that advertising and offers annoys users. One of the best known companies using spyware for e-commerce is Claria Cop. Legal spyware can be used by parents and other users, for control and supervision. Law institutions also use spyware for getting some information about criminals and criminals use spyware for crime. They get credit card number, collect passwords, names and addresses to perform carding or identity theft.

Spyware as program can not be defined as legal or not. Legal and illegal can be only usage of it. If spyware is bundled with other software and works without user's knowledge, then it's illegal. When user is informed about supervision and warned about supervision results, everything is legal.

There is a number of popular freeware that contain adware or spyware:
Odigo;
ICQ Surf;
Opera;
AdWizard;
Aureate Group Mail;
CuteFTP;
Dialer 2000;
FreeSolitaire;
GetRight;
Go!Zilla;
Grafula;
JetCar;
NetAnts;
ReGet;
WinEdit Zip Express.

But spyware and adware aren't irremovable problem. Spyware can be prevented and removed. The best way to escape spyware and adware is to be aware from freeware and P2P file sharing programs. Free music and video, cracks and cracked software are full of parasites. Always read End of User License Agreement before you install anything. To get full security on your privacy and computer system, buy firewall and anti-spyware software. Anti-spyware must have realtime protection feature and updates to increase your security. Scan your system at least once a week to avoid any parasites.