ad comes up on web site in bottom right corner?

[Donald]

When I go to some websites, an ad in bottom right corner comes up but its only on certain websites : newegg, facebook, realtor sites and a few others. I have ran virus scanners and malware scanner but did not find anything, starting to think its got to do with a cookie but cant seem to figure out how to stop it. Needing some ideas.

[Roger]

Many sites run banner advertising somewhere on the page. This is how they make money buy people clicking on them. If there is no X in the upper right corner of banner then you most likely are stuck with the ads. Some apps you can purchase the ad free site. Its not a virus. Just Capitalism.