Excellent article from @BI_Insider
In testing out a new diagnostic tool called Abine DNT+, we noticed that Facebook has more than 200 "trackers" watching our internet activity.
For example, cookies are tiny bits of software that web pages drop onto your device that identify you anonymously but nonetheless signal useful behavior about your background interests to advertisers who might want to target you. Facebook uses these types of cookies to activate the "like" buttons on other websites.
Critics call this spying. Advertisers call it targeting. That's how advertisers use Facebook to figure out when you're pregnant.
In an email to Business Insider, Abine privacy analyst Sarah Downey explained why users should pay more attention to trackers, and block them:
In addition to invading your privacy, these tracking requests can consume large amounts of data. And transferring lots of data takes time. Generally, the more tracking requests on a website, the slower that website loads. That's why DNT+ gets you surfing at 125% of the normal speed and with 90% of the bandwidth, compared to a browser without DNT+ running.
Equipped with this insight, an inquisitive Facebook user might be wondering why they wouldn't block all trackers and cookies alike. The Facebook page cautions:
Technologies like cookies, pixel tags ("pixels"), and local storage are used to deliver, secure, and understand products, services, and ads, on and off Facebook. Your browser or device may allow you to block these technologies, but you may not be able to use some features on Facebook if you block them.
Not all cookies are used for tracking or for other purposes, such as those used for Facebook's "like" button. Many are simply placed in order to store information for later use. But it is the broader scope of "requests" that present the larger issue. In simple terms, Downey explained that when you navigate to a website, your browser constructs that site by communicating back and forth with the server where the site information is stored. These communications are the “requests.”
But it isn't just the website you are visiting that makes requests for information: online trackers from other companies hidden on the site do it, too. They act as third parties on your computer: you can't see them without privacy software, you probably wouldn't expect them to be present, and you probably don't intend to share your information with them.
They request information like your geographic location, which other sites you’ve visited, what you click, and your Facebook username.
So, we set out to see just how much Facebook is watching our internet browsing activity. Using the Abine software, we tracked to what extent Facebook trackers increased for each new click. We started by cleaning out the browser cache and search history, and then went about using the browser like it was the start of a typical work day ...