Fastklick.biz website has been designed to promote potentially unsafe content on the Internet, like online gambling websites, pages with adult content, cracked software, fake updates installers, etc. This online tactic is based on sending browser notifications to mobile phones or computers of potential victims directly. The permission to do that is acquired by Fastklick.biz through a well-known trick. When visiting the website, users get the following pop-up window:
"Fastklick.biz wants to Show notifications
Your file is ready to download"
It is a fake message that claims that the user needs to click on a button within that window to be able to download a particular file. In fact, however, clicking on the button allows the website to display its sponsored advertisements on the user's screen. The advertisements generated by Fastklick.biz could hide many dangers for users' online security as they may contain links to corrupted websites or files.
If you keep seeing Fastklick.biz's pop-ups even after deleting its notifications permission from your browser, you should scan your PC for an adware infection. Adware's potential damage should not be underestimated as these Potentially Unwanted Programs (PUPs) often have data-tracking functionalities that can cause severe privacy issues.