Spyware / Adware
As if spam, viruses, and worms aren't bad enough. Adware and spyware are here to sap the remaining life out of your productivity and privacy.
Adware is software that displays advertisements on your computer. These are ads that inexplicably pop up on your display screen, even if you're not browsing the Internet. Some companies provide "free" software in exchange for advertising on your display. It's how they make their money.
Spyware is software that sends your personal information to a third party without your permission or knowledge. This can include information about Web sites you visit or something more sensitive like your user name and password. Unscrupulous companies often use this data to send you unsolicited targeted advertisements.
Prevent Unwanted Installation
Companies pushing adware and spyware are relying on two things: your desire for free software and your gullibility.
Make sure the programs you install don't contain adware. Many freeware programs do include adware. It's how the publishers make their money. If you're not sure, read the license agreement carefully (these are usually shown directly or through links as part of the installation process). Also, check the publisher's Web site very carefully. If you're still not sure, search for the name of the program and the keywords adware or spyware. If you don't find any postings about it, then you're probably OK.
Install a pop-up blocker to prevent adware and spyware pop-up windows. Much spyware installs after you click a deceptive link in a pop-up browser window. Install a pop-up blocker, and you won't even be tempted to click those links. Pop-up windows are annoying time wasters anyway, so you'll thank yourself later. If you're a Windows XP user, upgrade to the latest service pack (Service Pack 2) which includes a pop-up blocker for Internet Explorer.
Don't unwittingly install adware or software. If you do click what seems like a innocuous link, and then you see a dialog box similar to the one shown in Figure 1, don't click the Yes button to install the software. This dialog box is your last line of defense, and you should only install programs from the Internet that you chose to install. This is akin to giving someone your credit card number who calls you at home. It's a different story if you called them. Installing Windows XP service pack 2 will also provide some help by suppressing unsolicited downloads of ActiveX controls (a popular vehicle for spyware).
Figure 1
Popular Free Antispyware