What Are Cookies? Definition, History, Different Types, and More

The Neeva Team on 08/02/21

We’re not talking about the type of cookies that come out of your oven. Browser cookies—also known as HTTP cookies, internet cookies, or just “cookies”—have a huge impact on the way that we experience the internet, but when they’re being used, and how they work, can be unclear.

What are cookies?

A cookie is a small amount of data stored on your computer, tablet, or phone, created by and read by website servers. “Cookies were developed during a time when most web usage was anonymous,” says Sridhar Ramaswamy, cofounder of Neeva. “They became a way for websites to know about you.”

Cookies are kind of like nametags, in that they allow a website to recognize you, without having to store information about you on their own servers—whenever you visit a site, it sees the cookie on your device and knows who you are.

First-party cookies vs. third-party cookies

There are two main categories of cookies: first-party cookies and third-party cookies. Cookies are always associated with a particular domain (the name of a website). First-party cookies match the domain name of the website you’re currently browsing, while third party cookies are attached to a different domain name.

Third-party cookies have many different uses, but the most notorious are cross-site tracking cookies. Tracking cookies stitch together users’ activity across different websites, recording user browsing history, usually to serve targeted advertisements. Any website that partners with the third party can read and modify that cookie, giving some advertisers like Google and Facebook the ability to track you across millions of websites with the Google Display Network and the Facebook Pixel.

How do cookies work?

Here’s how websites use cookies to recognize visitors.

When you visit a website for the first time, it leaves a small text file known as a cookie on your device. This file can contain personal data such as:

  • A user identification code,
  • Customized preferences,
  • A record of which web pages you’ve visited on that domain.

The next time you visit that website, it recognizes the cookie on your web browser. This allows the site to “remember” who you are and any preferences you selected on your last visit without storing this information on its own servers.

Every time you visit that site, your cookie can be updated based on the way you interact with the website.

How are cookies used?

There are three main ways that websites use cookies.

  1. Session management: Everything a web server needs to remember in the course of a single browsing session, such as your login and authentication information, and the contents of your shopping cart.
  2. Personalization: The tailoring of your experience while navigating a website, such as user preferences and settings.
  3. Tracking: Recording and analyzing user behavior. This is usually done to either improve your experience on the site or for advertising, including targeting and retargeting.

How long do cookies last?

One of the ways cookies are commonly categorized is by their expiration date.

Session cookies automatically disappear at the end of a browsing session, as soon as you exit your web browser. For example: The items in your online shopping cart may disappear after you exit the browser window.

Persistent cookies remain on your device until they hit a predetermined expiration date, set by the website that placed the cookies. For example: A site that requires login credentials remembers your username, even after you exit the browser. The length of expiration varies, and can be anywhere from a few seconds to years.

Zombie cookies store a backup of themselves in a location other than where cookies are normally stored. When you delete cookies, zombie cookies will make a new version of themselves, making them incredibly hard to delete. These are typically used for targeted advertising: In 2016, Verizon settled with the Federal Communications Commission regarding its use of zombie cookies for this purpose.

A brief history of cookies

The introduction of cookies changed the internet forever, transforming it from an anonymous venue into an individual experience for every user. But the benefits of personalization were soon met with concerns about privacy.

  • 1994: Lou Montulli, an employee of what would later become Netscape Communications, invented the “persistent client state object,” which he nicknamed cookie, after “magic cookies” (a term for exchanging small pieces of code for identification purposes). Netscape’s cookie was first used to create a virtual shopping cart. Soon after, marketers began using cookies for digital advertising purposes.
  • 1996: An article in The Financial Times titled “This Bug in Your PC Is a Smart Cookie” alerted the general public to the existence of cookies.
  • 1997: After two years of work, the Internet Engineering Task Force (IETF) set the first standard for cookie usage, which did not support the use of third-party cookies.
  • 2002: The European Union e-Privacy Directive was the first major privacy law that required that users be able to refuse cookies.
  • 2017: Apple began blocking the use of third-party cookies for tracking purposes on its browser, Safari.
  • 2018: The European Union introduced the General Data Protection Regulation (GDPR), which requires advertisers to get users’ consent to place third-party cookies. The GDPR applies to any company that collects personal information about people who live in the European Union, regardless of where the company is based. (When you visit a website and see a pop-up announcing “this site uses cookies,” you’re seeing the effects of GDPR.)
  • 2019: Mozilla announced that it would block cookies from third-party trackers on its browser, Mozilla Firefox.
  • 2019: Google launched its Privacy Sandbox initiative, which includes phasing out third-party cookie support on the Chrome browser by 2023.

The pros and cons of cookies

Cookies get a bad rap due to their role in online advertising. But they’re actually not all bad—and can be more privacy-friendly than the alternatives. Here are the biggest pros and cons of using cookies:

Benefits of cookies

  • Cookies are stored on users’ computers, rather on a server, which keeps user data local and requires less storage capabilities from websites.
  • Users have the power to block and clear cookies whenever they want; this is not necessarily the case with newer advertising technologies like fingerprinting.
  • Cookies allow for continuity between different services and devices, creating a seamless user experience and saving time.

Drawbacks of cookies

  • There’s no limit to the amount of cookies that can be placed on user devices, leading to all kinds of unnecessary tracking and invasive advertising.
  • Deleting or blocking all cookies can hinder website functionality, forcing users to make a choice between privacy and user experience.
  • Cookies allow major advertisers like Google and Facebook to follow users’ behavior around the web.

How to change your cookie settings

When you visit a new site, you will likely see a pop-up or banner alerting you to the fact that the site uses cookies. This new development is thanks to the GDPR, which requires websites to get users’ consent before using third-party cookies, and the California Consumer Protection Act (CCPA), which requires websites to let users know how their data will be used, and to provide them with an option for opting out of the sale of their personal information.

If you’re concerned about tracking cookies in particular, you can either use a browser that automatically blocks third-party tracking cookies, such as Safari or Firefox, or you can install a browser extension that blocks tracking cookies, such as Privacy Badger or Neeva’s tracking extension.

You can also delete cookies or change your cookie settings in your browser.

Here’s how to turn cookies on and off if you’re using Google Chrome:

  1. Open Chrome.
  2. Click on the three dots in the top right corner of the window.
  3. Select Settings.
  4. Under “Privacy and security,” select “Cookies and other site data.”

If you’re using Safari, follow these instructions:

  1. Open Safari.
  2. In the menu bar, select Safari > Preferences.
  3. Select the Privacy tab.



Neeva is the world’s first private, ad-free search engine, committed to showing you the best result for every search. We will never sell or share your data with anyone, especially advertisers. Sign up today and try Neeva for yourself: neeva.com/signup.