Opt-out means that you tell a company that you don't want them to use your information for certain purposes or sell it to others. When you opt-out of online profilers or dataminers you are setting a cookie, a small piece of data, that does not allow them to track your surfing habits as you move about the web.
Online advertisers cannot see what is on your computer, but by profiling your surfing habits they hope to serve up better and more targeted ads to consumers. Because cookies contain what sites you've surfed to and probably any transactions you've made, companies can and do read that information off your computer so they can target their marketing efforts toward products you're more likely to buy. Advertisers argue that online profiling makes life easier for consumers because consumers don't see unwanted ads.
It is natural to understand that companies need advertising to survive and when used judiciously and non-intrusively we support the use of Internet advertising. However, we feel that privacy is privacy no matter how you slice it and consumers have a right to opt-out of being profiled.
