Adware is computer software that displays advertisements on your PC. These are the ads that 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. This is 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 the Web sites you visit or something more sensitive such as your user name and password. Unprincipled companies often use this personal information to send you unsolicited targeted advertisements.
The main problem that most people notice with Adware and Spyware is that they cause performance issues with their computers. For example, Internet Explorer or Firefox might not work properly any more, your computer might hang more frequently, or your computer might slow down significantly.
Unauthorized adware and spyware usually install on your computer covertly by using one of two methods:
1. Tricking you into clicking a link that installs it
Links to spyware can be deceptive. For example, a Web site that's trying to push spyware onto your computer might open a window that looks like a Windows dialog box, and then trick you by installing when you click a Cancel button to close the dialog box. Sometimes, spyware pushers will put a fake title bar in an empty window, and then install spyware when you try closing the window.
2. Installing freeware that includes it
For example, you might install a free file-sharing program that surreptitiously installs spyware on your computer. File-sharing programs can be a major source of adware.
Once installed, spyware can transmit your personal information and download advertisements 24 hours a day. It can also hijack your browser settings, such as your home page or search page.
Most popular antivirus products now include adware and spyware scanning. For example, the latest versions of McAfee VirusScan, Norton AntiVirus, Zone Alarm Security and Trend Micro PC-Cillin now scan for adware and spyware.
Also, most Internet service providers (ISP's) have taken some steps to protect their customers from adware and spyware attacks.
Of course, to take advantage of the built-in protection that antivirus products provide, you have to get to the latest versions, and keep the anti-spyware/adware signatures up to date.
Companies pushing adware and spyware are relying on two things: your desire for free software and your gullibility. So what steps can you take to prevent the installation of most adware and spyware:
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 Google Groups for the name of the program and the keywords adware or spyware. If you don't find any postings about it then you are 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. Fortunately the latest internet browsers such as Firefox 2.0 and Internet Explorer 7 include very effective pop up blockers.
Don't unwittingly install adware or software. If you do click what seems like a innocuous link, and then you see a dialog box don't click the Yes button to install the software. If in doubt, however, do not proceed.
There is software specifically designed for detecting and removing spyware and adware.
At QBS PC Help we use several free software tools to combat Adware and Spyware on our own computers. These include:
For checking spyware, adware and rootkits Prevx CSI is a new security tool that we are using and it works well!
And for clearing Windows temporary files, browser or start menu run histories and cookies we love CCleaner.
You can find more adware and spyware removal tools at the Anti-Spyware Guide. This Web page includes links to popular spyware removal programs, as well as a number of useful articles.