The answer is simple: spyware. "Spyware" refers to a class of sophisticated computer programs that are surreptitiously installed on your computer by clever internet marketing geeks so that they can deliver advertising directly to you and take control of your machine, which can slow down or sometimes completely stall your internet access temporarily. Spyware evolved sometime around the year 2000, right around the time that email began losing its luster as an effective marketing tool. Faced with declining responses to their spam, top nerds from around the globe joined together and invented a new way to throw advertisements for mortgages, discounted brand names, and cleavage right in your face so that you wouldn't be able to hide behind your spam filter.

How does spyware get onto your computer? Spyware gets installed on your machine many different ways, and savvy programmers are coming up with new ways to infect you every day. One way they do it is by bundling it with legitimate software programs that you install on your machine. You may have ordered or downloaded some sort of shareware or other software for a legitimate purpose that had spyware attached to it. So, when you installed the software, you installed the spyware along with it. Sometimes, anti-spyware software is actually spyware itself!

The most common way that spyware is installed on your computer is by direct download from a website you're visiting, unbeknownst to you. How does this happen? Well, as soon as you arrive at the website, the website begins transferring the spyware to your computer. Internet Explorer is supposed to protect you against unauthorized downloads. This is no problem for spyware developers, as they know how to attack the holes in your firewalls and anti-virus software. Also, they often send a pop-up box to you while you're online that appears to be an Internet Explorer dialog box and says something like "your browser resources are low, click here to optimize your access," and then when you click, spyware is downloaded to your machine.

Once installed on your machine, how does spyware actually work? How does it deliver its insidious, unwelcome contest to your computer? Well, it infects your operating system (Windows, for example), and then begins to direct your internet usage once you go online. It delivers pop-up ads to your browser. Sometimes, it redirects you to the website of its choice when you type an address into your browser. For example, you type in the web address for Yahoo, and the spyware then tosses you over to a website for a company that the spyware author is promoting.

The most annoying and potentially dangerous function of spyware is that it keeps a record of all of the websites you're visiting as you're surfing the net, and then it sends this information back to the spyware company so they can then send you targeted advertisements that match your tastes. Sometimes, spyware is used purely for criminal purposes, such as stealing your credit card information or social security number whenever you enter this information into an order form or email form so that it can be transmitted back to the hacker. The hacker then uses your credit card number for a few days, and maybe uses your social security number to temporarily hijack your financial identity. This is known as identity theft, and it has become much more prevalent during the past several years.

To protect yourself, you can install legitimate spyware protection software that can spot these programs and delete them from your hard drive. One of the most popular spyware programs is Adaware. For AOL users, AOL comes with a spyware detection program that you can use. I recommend that you call your internet service provider, talk to their technical support staff, and ask them which software program they recommend for detecting and deleting spyware from your computer.