What is a website cookie?

A cookie is a small bit of data stored as a text file on a user’s browser. The main purpose of a cookie is to associate this piece of data with a specific user in order to help a website keep track of a user’s visits and activity.

For example, if you visit a website, a cookie will be placed into your browser. If you leave the website and come back after a while, that cookie will be used by the website to recognize that you are the same user who visited the site previously.

Photo source: Primedesignsolutions.com

What does a website cookie contain?

A cookie contains at minimum two pieces of data:

• a unique user identifier
• some information about the user (browser behavior, interests, demographics)

Type of cookies

• Session cookies - temporary cookies that are active while you are navigating a website; once you live the website, they disappear;
• Persistent cookies - longer-term cookies with an expiration date;
• First-party cookies - they are created by the website you’re currently visiting;
• Third-party cookies - cookies added by other domain;

They also may be known as: HTTP cookie, web cookie, internet cookie, computer cookie, or browser cookie. 

Resources:

• Browser Cookies: What Are They & Why Should You Care?
• What are cookies?