Stop Facebook from tracking everywhere you go online

File/AP

You wouldn’t let a private company, or the government, strap a GPS unit to you so it could track what stores, businesses and parts of town you visit. But that’s exactly what online companies do for your Internet travel, and most people don’t even realize it.

You do see the effects though. Usually it’s an ad for a product you looked at one time that follows you from website to website for weeks. That’s annoying, but behind the scenes something much scarier is going on.

Many online companies are members of ad networks. Each ad network puts a bit of code called a cookie on your computer. When you visit one of the member sites, the site recognizes the cookie and lets the ad network know where you are.

Even worse, the member sites share what you do on their sites to build a database of what you like and don’t like. This makes it easier for the ad network to send you ads that it thinks you’ll click on.

Any website sending advertisers what you’re doing is worrying, but when you get Facebook into the mix, things get much worse. That’s because most websites have to figure out what your activity means. On Facebook, you tell them exactly what you’re thinking.

Every “like,” news story click, status update and photo caption is a bit of information that advertisers would love to add to your file. And you’d be surprised how much money it can make them.

In 2013, online tracking and targeted advertising practice helped Internet advertisers rake in a staggering $42.8 billion. And the 2014 numbers will probably approach or pass $50 billion.

Naturally, you don’t see a penny of it. You’re just concerned with what happens to your information if a shady employee or hacker gets a hold of it. Or you just don’t like the idea of being tracked.

That’s where we find the one good thing about ad networks. Instead of visiting every company online and telling them you don’t want to be tracked, you can just opt out of the ad network and it applies to every company in that network.

Facebook and 176 other major companies are part of the Digital Advertising Alliance. You can use a tool on the DAA’s website to opt out of “online behavioral advertising.”

The tool will scan your computer to see what companies are already customizing ads to target you. It can also tell if you’ve opted out of any online tracking for those companies in the past.

It’s simple to choose a few companies and sites, like Facebook, where you don’t want to see targeted ads. Or you can click the “Choose all companies” button at the bottom to opt out of targeted ads for every participating network member. Simple!

Now, opting out also doesn’t stop these sites from collecting some information about you, but it does mean they won’t share it with other companies. That limits what any one company potentially knows about you, and keeps a single ad company from building up a profile.

Because tracking is cookie-based, so is opting out. The site will put a cookie in your browser saying you don’t want to be tracked.

This means you’ll need to run the tool in every browser you use so they’re all covered. Facebook is one exception. If you opt out in one browser, it will honor your opt-out whenever you log into Facebook, no matter the browser.

There are still many companies online that don’t participate in the Digital Advertising Alliance, so opting out won’t change the way they behave. One way to put a stop to them is to disable third-party cookies in your browsers - you’ll just need to wait until after you run the DAA’s tool or it won’t work correctly.

Ready to stop the tracking? Click here to visit the Digital Advertising Alliance’s tracking opt-out tool.

Your browser isn’t the only way advertiser can track you on your mobile gadget. There are also ads in apps. Click here to find out how to opt out of all targeted ads on Android and Apple.

You shouldn’t only be worried about what advertisers and Facebook can see about you. Strangers could find out more about you than you think if you have the wrong Facebook security settings. Click here to learn how to lock down your Facebook profile from beginning to end.

On the Kim Komando Show, the nation’s largest weekend radio talk show, Kim takes calls and dispenses advice on today’s digital lifestyle, from smartphones and tablets to online privacy and data hacks. For her daily tips, free newsletters and more, visit her website at Komando.com. Kim also posts breaking tech news 24/7 at News.Komando.com.