Ad supported software, often called Adware or Advertising Supported Software, is used when referencing any type of program that downloads or displays unwanted banner advertisements in the software being used. Adware is often bundled with software a computer owner purchases. The authors of a program sometimes include adware in their software to recover development costs, or to be able to provide the product for free or at a discounted price. Adware can be designed to collect data on which sites the user visits, send this data back to the company and deliver advertising based on the information. Though the advertisements produced by adware may be seen as an annoyance, a distraction, or an invasion of privacy to the user, the income the developer receives may help them to maintain, upgrade and continue to develop more products. Often, after using a free software product that includes adware, a user may opt to purchase a registered or licensed version without adware to remove the ads. This adware-free product may also have additional functionality.

However, adware can also contain or be classified as spyware, a type of malware that is considered by many to be privacy-invasive. Spyware can steal a user’s information or corrupt the user’s system files. Though adware companies may have a Privacy Policy stating that no sensitive or identifying information will be collected, there is usually no way for the user to be completely sure that he or she remains anonymous. Therefore, because of privacy concerns and the prospect of malicious adware, antivirus software today detects and removes both adware and spyware.

What Is Spyware?
Spyware surreptitiously monitors your computer and Internet use. Some of the worst examples of spyware include keyloggers that record keystrokes or screenshots, sending them to remote attackers who hope to glean user IDs, passwords, credit card numbers, and other sensitive information.

Most often, though, spyware takes a more benign (but still quite offensive) form. The information gathered, often referred to as “traffic data”, can consist of monitoring the web sites visited, ads clicked, and time spent on certain sites. But even in its more benign form, the collected data can morph into something far more insidious.

Spyware tracking can link your system’s unique numerical hardware ID (MAC address) and IP address, combine it with your surfing habits and correlate it with any personal information gathered when you registered for free programs or entered data in web forms. The spyware purveyor then trades this information with affiliate advertising partners, building an increasingly complex dossier on who you are and what you like to do on the Internet.

Has this ever happened to you? One day you’re browsing the Internet as normal. The next day your browser’s homepage has been changed to some off-color site and your desktop is serving up some program you don’t recall installing.

Termed adware, the Internet is filled with programs that hijack your PC for profit, most hidden inside so-called “free” downloads and pop-up ads that forcibly install software on systems with improper security configurations.

This doesn’t mean that all free downloads are bad or that all pop-ups try to surreptitiously install software. It does mean, however, that you’ll want to play close attention to both the licensing agreement of free downloads and the security settings in your browser.

What Exactly Is Adware?
Generally speaking, adware is a program that installs an additional component that feeds advertising, often by delivering pop-up ads or by installing a toolbar in your browser.