Question: I try to keep my Windows 10 PC free of unwanted software by running PC security (Malwarebytes) and cleaning (CCleaner) programs on my Windows 10 PC. I also use the DuckDuckGo search engine that doesn’t create profiles of its users.

Yet when I log into my Gmail account, my PC acquires about 200 to 300 web trackers (a type of software that monitors your online activity) that I have to remove using CCleaner. If I log into Facebook, I get another 300 to 400 trackers. If I spend a couple of hours online, I can accumulate 20,000 or more trackers, which is far more than my old Windows 7 PC gets. Why does Windows 10 attract more tracking software, and what can I do to maintain my privacy? — C.G., Minneapolis

Answer: There are several reasons that your Windows 10 PC is overrun by web trackers, bits of software code that follow you online to help marketers learn more about you. Here are a few:

Web trackers make money. Nearly all commercial websites use them to create an elaborate profile of your tastes and habits, a profile that the websites can use themselves or sell to others.

Your online movements are tracked by cookies (bits of code left in your web browser), Google and Facebook tracker software (that follows you even when you aren’t on their websites), session recorders (that record everything you do on a website), key-loggers (that record what you type into text boxes on a website, even if you don’t submit anything), beacons (invisible objects in a web page that record how many times you viewed that page) and “fingerprinting” (a record of the technical details of your computer that can be used to identify you.)

While privacy advocates are aware of web trackers, most people aren’t. As a result, web tracking keeps expanding. A recent study showed that 87% of the most popular websites now track your movements, whether you sign in to the website or not (see tinyurl.com/yyy5qyas). (View the web trackers on any website at tinyurl.com/y2em59e6).Windows 10 might attract more web tracker software, because it collects more personal information about you than earlier versions of Windows did. Microsoft shares some of that information with advertisers.

Until recently, web browsers didn’t offer much protection against web tracking.

Here are the best ways to block web trackers:

Get a new web browser with more defenses. The latest versions of the four most popular browsers — Google Chrome, Microsoft Edge, Mozilla Firefox and Apple Safari — have improved (but not perfect) anti-tracking features. A reviewer of the latest Safari browser reported that it blocked 90 web trackers in five minutes of online activity (see tinyurl.com/y8ggnzat). But be sure your browser’s anti-tracking features are turned on (see tinyurl.com/y2pllywb).Adjust the privacy settings in Windows 10. The Windows 10 settings you may want to change (see tinyurl.com/y5othu62) include the “advertising ID” (monitors your online travels for advertisers), “location tracking” (helps advertisers localize what they promote to you), “Timeline” (keeps track of what you’re doing so that you can switch from one PC to another without interruption) and Cortana, the Windows 10 digital assistant (monitors your location, e-mail, contacts, and calendar, and keeps a record of every “chat” you’ve had with Cortana.Add more anti-tracking software to your web browser. Top-rated programs include DuckDuckGo Privacy Essentials, Privacy Badger and Ghostery (see tinyurl.com/yb3a8ccx).