There are many different forms of spyware and although some does not appear to do much, all spyware uses your computers resources and thus can decrease your computer's speed sometimes slowing it to a complete halt. Most spyware also uses your bandwidth when you are online which slows your internet connection and can cause you not to be able to browse or email at all.

Here are some of the most common types of spyware:

Adware:
The most common form of Adware is pop-ups. Nearly every computer user has encountered a pop-up at one time or another. Some Spyware removal companies actually use pop-up Adware to get you to buy their products so you can remove their Spyware from your computer. One of these is the pop-up which says "Your pc is infected with spyware. Click here to remove it". There are also banner ads on websites which say the same thing. Can you really trust a Spyware remover that uses Spyware to advertise?
Other forms of Adware are banner advertisements in software. Some of these are legal whilst others aren't. The illegal forms of Adware normally monitor your computer usage and browsing habits to send you targeted advertising.

Browser Hijacker:
This is a program that changes some settings in your browser. The most common is to change your default home page so you are redirected to a different site every time you open your browser. In some cases the hijacker will not let you visit any site except for the ones it wishes you to go to. Some forms will also change your default search page so when you type a URL that doesn't exist you will be redirected to a pay per search site. Browser Hijackers may also log your browsing habits and transmit your surfing habits to an agency or person for analysis.

Identity Theft:
Although this is not an actual type of Spyware it is worth mentioning as it is now becoming a larger and larger problem. Criminals are using internet worms and trojans to gain access to your computer and then scanning your whole system until they know enough about you that they can give your identity to someone else, usually a criminal. This person can then masquerade as you until you are caught for his/her crimes.

Modem Hijacker/Dialler/Dropper:
This will alter the username/password and phone number in your dial up connection. When you try to dial, it will try to connect to a different connection which is usually some form of porn site which charges high rates (average $5 a minute) for the connection. This charge will appear on your normal phone bill and since your telephone company had nothing to do with it you will be liable for the charges. A Dialler can also dial without your knowledge just by having your computer left switched on. A Dropper will actually wait until you connect and then disconnect you and dial a different number usually without you even knowing it has happened. If you discover anything changed in your dial up connection you should remove the phone cable from your pc/modem until the spyware is removed.

System Monitors:
This form of spyware enables someone to monitor everything that happens in your computer and then to send the data away to be analysed. This includes:
          -Key Loggers - A program that logs every key that is pressed on your keyboard and transmits the information to someone who can then search through the data for credit card details, usernames, passwords etc.
          -Screen Recorders - This software takes a screen shot of your screen every few seconds and then sends the data off so someone can see everything you have done on your computer.
          -Chat monitors - These log details of any chats done via most of the popular chat programs. These include MSN messenger, Yahoo messenger, AOL and even Trillian.

ParasiteWare:
If you are a webmaster and have a site that contains affiliate tracking links then this will overwrite those links replacing them with someone else's so the intruder will get paid instead of you. The worst of this will actually place a redirect between the link on your site and the actual site so you do not even know someone is being redirected to the wrong site unless you click the link yourself.

Remote Administration:
This is when someone can control your computer from another location just like having a Trojan installed.

Trojan Horse:
These are designed to steal or encode your computer data and to destroy your system. Some Trojan horses allow unrestricted access to your computer whenever you're online. This can allow the person to control your whole pc - adding/deleting files, installing programs and even controlling your mouse.

Web Bugs:
A graphic on a Web page or in an email message determining who viewed the message or web page, when they did so, how many times, how long they kept the message open, etc. Web Bugs are often invisible (due to them normally being very small) to try to hide the fact that you are being monitored.

 

If you would like to add to this list then please email me.