Tracking cookies: What are tracking cookies and how do they work?

May 6, 2021

Cookies are small text files that websites save to your browser. These files contain data about you and your online browsing activity.

When you visit your favorite weather site, for instance, a cookie might remember that you searched for the temperatures in Chicago last week. When you log back on, the site will show "Chicago" as a recommended city for your next weather search.

Or maybe you log onto an athletic apparel site. A cookie might remember your log-in information so that you don't have to retype it or remember it each time you want to buy new workout clothes.

There are two main types of cookies, first-party and third-party. First-party cookies live on the site you are visiting. Third-party cookies originate from a site that you aren't currently on. It is these third-party cookies that are also known as tracking cookies because they track you as you roam the internet.

Tracking cookies are the ones that send targeted ads to websites that you visit, with the goal of persuading you to return to sites you visited in the past or buy products from advertisers that you've clicked on before. But are they dangerous? That depends on how much you value your privacy when browsing the web.

How do tracking cookies work?

Tracking cookies are mostly used for marketing and advertising purposes. The goal is to increase the odds that you’ll purchase a product or service.

Say you are ready to take a road trip to the mountains. You might start searching the websites of communities around your destination. You might also log onto the sites of attractions, restaurants, and hotels in that area.

Then, when you surf onto your favorite news sites, entertainment blogs, and community sites, you start seeing ads from the same hotels and attractions. This is how third-party tracking cookies work: The sites you visit save them on your browser. They then send targeted ads to you as you scour the internet.

What information do tracking cookies store?

Because tracking cookies are mostly used by companies that want to market their products or services to you, they mostly store information about your online browsing activity.

These cookies will store a list of sites you've visited and track what pages you looked at when on them. They also store any products you might have clicked on or purchases that you've made. Again, the goal is to collect any information that will make it easier for companies to sell you their goods and services.

Tracking cookies also track your IP address and your geographic location. This last bit of information is important for marketers that might want to show you ads for upcoming concerts or events in your area, tickets for your local baseball or football teams, or sales taking place at stores near you.

Are tracking cookies dangerous?

Tracking cookies collect plenty of information about you. But does this make them dangerous? That largely depends on what you consider dangerous.

Tracking cookies won’t damage your computer or other devices and won’t place malware or adware on them. In that respect, they are safe. But if you don’t want companies, government bodies, news organizations, or social media sites tracking your browsing activity, you might consider tracking cookies to be a violation of your privacy.

How to prevent tracking cookies

Fortunately, if you don’t like the idea of cookies tracking your online activity, you can disable them.

Typically, when you visit any website, it will store at least one cookie — a first-party cookie — on your browser. This cookie remembers your basic activity on the site. When you visit a site for the first time, it will also give you the option to limit cookie activity. Some sites will allow you to disable all third-party cookies. If you want to keep your browsing activity away from the eyes of companies and social media sites, select this option when sites give you the choice.

You can also set up your browser so that it will automatically disable third-party tracking cookies. The directions to do this differ depending on the browser you are using. 

Microsoft Edge: To disable third-party cookies on Microsoft Edge, click the gear icon in the upper-right-hand corner. Select the “Settings” option in the next menu. Click “View Advanced Settings.” In this menu, find the “Cookies” heading. Select “Block only third-party cookies.”

Chrome: Click the three dots in the upper right-hand corner of the browser. Next, click “Settings.” In this menu, click “Show advanced settings.” Click on the “Privacy” heading and then click “Content settings …” In this menu, check the box next to “Block third-party cookies and site data.”

Firefox: Click on the three lines in the Firefox browser’s top right-hand corner. In the "Options" menu, choose "Privacy & Security." On the right-hand side of the page, you’ll then see Firefox's "Content Blocking" choices. Check the circle next to the "Custom" option. Next, select the checkbox "Cookies." You can then choose "All third-party cookies" in the drop-down list.

Laws regulating tracking cookies

The days of third-party cookies might be coming to an end. Google, for instance, has announced that it will stop using third-party tracking cookies on its Chrome browser by 2022. That’s big because Chrome is such a widely used web browser.

But it’s not just private companies that are taking steps to limit third-party cookies. Governments, too, have enacted legislation to create civil and criminal penalties for companies, marketers, and others that don’t inform consumers that their websites are using cookies.

This includes Europe’s General Data Protection Regulation, or GDPR, which regulates how personal information is collected, stored, and eliminated by multi-national companies. It also includes the California Consumer Privacy Act, or CCPA, designed to protect the privacy of California consumers. Companies that violate these laws by not telling consumers that their sites are tracking them with cookies can face hefty fines.