What Are Internet Cookies? A Complete Guide to How They Track and Store Data

Don’t click ‘Accept all cookies’ the next time you see the privacy pop-up window.

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Last Updated: Oct 28, 2024
A graphic design depicting internet cookies as literal cookies in a web server that’s connected to a laptop
Not all cookies are good — internet cookies contain information you don’t want outsiders to get their hands on.

Cookies are essential to modern web browsing, acting as a digital footprint of your website interactions. They’re key to personalizing content, maintaining user sessions and providing tailored ads. While they offer convenience, they also track significant amounts of user data. In this guide, we explore internet cookies, how they work, the various types of cookies and their implications for your privacy. We’ll also provide tips for managing cookies effectively to control what information websites can access.

Overview of Internet Cookies

  1. What Are Internet Cookies?
  2. Types of Internet Cookies
  3. How Internet Cookies Track and Store Data
  4. Privacy Concerns and Regulations
  5. How to Manage Cookies

What Are Internet Cookies?

An internet cookie, or HTTP cookie, is a small piece of data sent from a website to your browser. The browser stores this data and sends it back to the same website on future visits. This allows the website to “remember” you and your actions, such as login details, items in a shopping cart or preferences.

Cookies were first introduced in 1994 by Netscape Communications to enable websites to maintain stateful information, such as whether a user was logged in or had visited the site before. Since then, their usage has evolved dramatically and has become integral to website operations.

Today, cookies are used for a variety of purposes, from saving login credentials to enabling websites to display personalized advertisements. However, as they collect data about your behavior, they also raise significant privacy concerns (We’ll dive into that more later.).

Types of Internet Cookies

Iconography of the different types of internet cookies
Not all cookies are bad — some are necessary, so it’s important to identify which ones are good.

There are several types of internet cookies, each with its specific function. These include session cookies, persistent cookies, first-party cookies and third-party cookies. Each type serves a different purpose and varies in termas of how long they remain active and who can access them.

Session Cookies

Session cookies are temporary and are erased when you close your browser. These cookies are primarily used for things like keeping you logged into a website during a single session. For example, if you’re shopping online, a session cookie may remember what’s in your shopping cart until you complete your purchase. However, once you leave the site or close your internet browser, the session cookie disappears, and you’ll need to log in again or re-add items to your cart on your next visit.

Persistent Cookies

Persistent cookies, as the name suggests, remain on your computer even after you close your browser. They have an expiration date set by the website, which can range from a few days to several years. These cookies are used to remember login credentials or language preferences, so you don’t have to input this information each time you visit a website. Persistent cookies are also used for tracking users across different sessions, allowing websites to understand return visitors’ behavior and improve their services accordingly.

First-Party Cookies

First-party cookies are set by the website you’re visiting. They’re primarily used for things like remembering login details, user preferences and personalizing content. Since these cookies are set by the domain you’re visiting, they’re generally considered less invasive than third-party cookies because they’re not shared across websites.

Third-Party Cookies

Third-party cookies are set by domains other than the one you’re visiting. These cookies are most often used for online advertising and tracking across different websites. For example, if you visit a news website that displays an ad from a different company, the ad network can place a cookie in your browser. This allows them to track your activity across various sites and serve you targeted ads based on your browsing history. Third-party cookies are the primary reason for the growing concerns about internet privacy and data security.

How Internet Cookies Track and Store Data

Cookies play a critical role in tracking and storing data online. Every time you visit a website, a cookie records your actions, such as pages visited, products viewed and any personal information you may have provided. Cookies store this data locally in your browser and send it back to the website upon request.

One of the most prevalent uses of cookies is in online advertising. Third-party cookies, in particular, enable advertisers to track you across multiple websites and create detailed profiles of your browsing habits. This data is then used to serve personalized ads tailored to your interests, significantly increasing the effectiveness of online marketing campaigns.

Internet Service Providers (ISPs) can also use cookies to monitor your online activities, although they typically rely on other methods, like DNS tracking. These tracking methods are often used to maintain data caps per your internet plan. Additionally, cookies are used in various web services, including keeping users logged in, maintaining preferences across visits and analyzing website performance for optimization.

Privacy Concerns and Regulations

A graphic design of a computer screen showing a privacy pop-up window
Privacy pop-ups appear on almost every website, so make sure you either customize or reject cookies if you don’t want your online activities and personal information stored.

Cookies’ ability to collect and store vast amounts of personal data has triggered widespread privacy concerns. In response, governments around the world have introduced regulations to safeguard user privacy and limit the use of cookies without explicit consent.

In the U.S., the California Consumer Privacy Act (CCPA) restricts how websites use cookies and other tracking technologies. Websites must inform users about the data collected and allow them to opt out of having their personal information sold to third parties. Similar regulations are being adopted in other regions to ensure that users have control over their data. Other states that have worked to implement similar laws include Colorado, Connecticut, Virginia and Utah.

Some web browsers, such as Safari and Firefox, have implemented measures to block third-party cookies by default, limiting advertisers’ ability to track users across websites. While Google Chrome browser has announced plans to phase out support for third-party cookies, and has even taken some measures to do so, the company recently shared that it no longer plans to phase out third-party cookies.

How to Manage Cookies

Given the privacy concerns associated with cookies, it’s essential to understand how to manage them. Fortunately, most modern web browsers provide tools that allow users to control how cookies are used.

  • Adjusting Cookie Settings: In your browser settings, you can find options to block third-party cookies, clear existing cookies and manage cookie permissions on a site-by-site basis. For example, you may choose to allow cookies from trusted websites but block them from unknown or potentially harmful domains.
  • Using Browser Extensions: Several browser extensions can help you manage cookies more effectively. These tools block tracking cookies and provide insights into which websites are trying to track your data. Additionally, they can help you maintain privacy while browsing without needing to constantly adjust your browser settings.
  • Regularly Clearing Cookies: Another simple yet effective way to manage cookies is to regularly clear them from your browser. You can remove any unwanted cookies that may have been stored without your consent. Keep in mind that clearing cookies will also delete any saved login credentials and preferences, so you may need to re-enter this information on frequently visited sites.

Frequently Asked Questions About Internet Cookies

Should I accept cookies?

Accepting cookies depends on the type of cookie and the website you’re visiting. First-party cookies enhance your browsing experience. Third-party cookies are more invasive. These cookies are often used for targeted advertising, and they gather detailed information about your online behavior.

What happens if I refuse to accept cookies?

If you refuse to accept cookies, especially first-party cookies, certain website functions may not work as intended. Some websites may restrict access to features like video playback, personalized recommendations or interactive content unless cookies are enabled.

Which websites use a lot of cookies?

E-commerce websites, such as Amazon or eBay, often use multiple cookies to track what you’re browsing, save your shopping cart, and show product recommendations. Social media platforms like Facebook or Instagram also heavily rely on cookies to keep you logged in, show relevant content and serve personalized ads.

How do I see what sites are using cookies?

In browsers like Google Chrome, you can access cookie information by clicking on the padlock icon in the address bar. This will show you what cookies are in use and allow you to manage them individually. Certain browser extensions can give you a real-time breakdown of tracking cookies used by a website, showing which companies are collecting data on your browsing behavior.

Can websites track you without cookies?

Even if you block or refuse cookies, websites can still track you using alternative methods like browser fingerprinting, IP address tracking and device identification. Browser fingerprinting, for example, collects data on your browser settings, screen resolution, installed fonts and plug-ins to create a unique profile of your device.