Spyware is any application that collects information about your computer activities and then sends that information to another individual or company without your knowledge or permission.

Spyware arrives bundled with freeware or shareware, through email or instant messenger, just clicking on a WEB page, or by someone with access to your computer. Once on your drive, spyware secretly installs itself and goes to work (this is called Hijacking). Unlike traditional personalization or session cookies, spyware is difficult to detect, and difficult (if not impossible) for the average user to remove.

Spyware comes in many flavors including:

Trojan Horses
Trojans are malicious programs (or viruses). Trojans are designed to cause loss or theft of computer data, and to destroy your system. Some trojans, called RATs (Remote Administration Tools), allow an attacker to gain unrestricted access of your computer whenever you are online. The attacker can perform activities such as file transfers, adding/deleting files or programs, and controlling the mouse and keyboard. Trojans are generally distributed as email attachments or bundled with another software program.

System Monitors/Key loggers
System monitors are applications, most likely a virus, designed to monitor computer activity to various degrees. These programs can capture virtually everything you do on your computer including recording all keystrokes, emails, chat room dialogue, web sites visited, and programs run. System monitors usually run in the background so that you do not know that you are being monitored. The information gathered by the system monitor is stored on your computer in an encrypted log file for later retrieval. Some programs are capable of emailing the log files to another location.

Adware
Adware is advertising-supported software that displays pop-up advertisements whenever the program is running. The software is usually available via free download from the Internet, and it is the advertisements that create revenue for the company. Although seemingly harmless (aside from intrusiveness and annoyance of pop-up ads), adware can install components onto your computer that track personal information (including your age, gender, location, buying preferences, surfing habits, etc.). Most advertising supported software doesn't inform you that it installs adware on your system, other than via buried reference in a license agreement. In many cases the software will not function without the adware component. Some Adware can install itself on your computer even if you decline the offer.

Adware Cookies
Cookies are pieces of information that are generated by a web server and stored on your computer for future access. Cookies were originally implemented to allow you to customize your web experience, and continue to serve useful purpose in enabling a personalized web experience. However, some web sites now issue adware cookies, which allow multiple web sites to store and access cookies that may contain personal information (including surfing habits, user names and passwords, areas of interest, etc.), and then simultaneously share the information it contains with other web sites. This sharing of information allows marketing firms to create a user profile based on your personal information and sell it to other firms. Adware cookies are almost always installed and accessed without your knowledge or consent.

How to protect yourself

Anti-virus Software
Just because you are running an anti-virus (AV) program doesn’t mean you are protected. A file called “Virus Definition file” is updated regularly when new viruses appear. This file needs to be installed on your PC every time the updates occur. Most AV programs require that you purchase a yearly subscription to do this. If you are an FDU student, you can download and install Norton Anti-Virus with automatic virus definition updates for free. It can be downloaded here:
https://isweb.fdu.edu/secure/student_download/av_download.html

Windows Updates
Even if you are up-to-date with your Anti-Virus program, because of flaws in Microsoft’s operating systems, your computer may still be vulnerable. Each time Microsoft discovers a flaw, they publish updates on their web site that can be downloaded and installed. To update your computer, start Internet Explorer, click on “Tools”, and then click on “Windows Update”. Follow the instructions to install critical updates.
On Windows XP machine, it is a good idea to enable “Automatic Updates”. Right-click on “My Computer”, and then click Properties. A “System Properties” window opens, click on the “Automatic Updates” tab. Put a check mark in the box “Keep my computer up to date….. Select “automatically download the updates, and install them on the schedule that I specify.

Hosts File
This is my personal favorite. There is a file on your system called the hosts file. You can use a hosts file to block known spyware Internet locations. You can download, free of charge, a spyware blocking hosts file. For more info, go to: http://www.mvps.org/winhelp2002/hosts.htm

Anti-Spyware Scanners
Once spyware has been installed on your computer it can be difficult to remove manually. Several programs are available which will scan through your computer and remove spyware automatically.

Ad-aware (http://www.lavasoftusa.com/) Free
Spybot Search&Destroy (http://www.safer-networking.org/) Free
Similar to anti-virus software, these programs need to be updated regularly with the latest software.

Firewalls
A good software firewall will protect your computer from being attacked. It will block attacks from a remote location and also block software from hijacking your computers network connection. Windows XP has a firewall built in. It is recommended that you use one of the following:

Tiny Personal Firewall (http://www.tinysoftware.com)
Norton Personal Firewall (http://www.symantec.com/sabu/nis/npf/)
McAfee Personal Firewall (http://us.mcafee.com/root/package.asp?pkgid=103)
Zone alarm (http://www.zonelabs.com)