Because your internet traffic moves to and from your devices (computer, phone, tv, tablet) through your ISP, they can see where you go online. An ISP can see what sites you visit, how long you’re on them, your location and information about your devices. An ISP may not know the specifics of what you did on those sites (like what you bought, searched for or read) thanks to encryption, but they could make inferences about you based on the sites that you visited.  That personal data can be used to create detailed profiles about you. Why would ISPs do that? In short: this data is valuable.
因为您的互联网流量是通过 ISP 来进出设备（电脑、手机、电视、平板电脑）的，他们可以看到您在网上的活动。ISP 可以看到您访问了哪些网站，在上面停留了多长时间，位置和设备信息。由于信息加密，ISP 可能不知道您在这些网站上做了什么（比如买了什么，搜索了什么或读了什么），但他们可以根据您访问的网站做出推断。  这些个人数据可以被用来创建关于您的详细档案。为什么 ISP 会这样做？简言之：这些数据很有价值。