Every time you browse, you leave behind a digital trail that companies use to...

https://smart-wiki.win/index.php/What_Is_a_Passive_Digital_Footprint%3F_(And_Why_You%27re_Leaving_Them_Everywhere)

Every time you browse, you leave behind a digital trail that companies use to build a profile on you. This happens through invisible trackers that follow your activity from site to site