By now, you have probably heard the term internet cookies. Your first thought might be to think of delicious desserts sprinkled with melty chocolate. But in this case, they are just a useful tool used by internet people. Let’s take some time to learn a few things about this common tool that we all interact with on a daily or even hourly basis.


The handsome fella on the left is Lou Montulli, he is the creator of the HTTP cookie. The cookie was created in 1994 by Lou at 23 years old while working for Netscape. Lou thought it could improve the online shopping experience as there was no way to remember a user at they moved between website pages. He had this to say about cookies:

Without a session, each time a user clicked to move to a different page they would become just another random user with no way to associate them with an action they had done just moments ago. This is a bit like talking to someone with Alzheimer disease. Each interaction would result in having to introduce yourself again, and again, and again.

Other notable work, includes several browser innovations, such as the blink element, server push/pull, HTTP proxying, and encouraging the implementation of animated GIFS into the browser.

So what are cookies and why are they important?

In simple terms, cookies are small pieces of data that are stored on your browser as a text file. These are sent to your browser by the server you are accessing. For example, this file can help the server recognize you as the same logged in user. As in, you don’t have to continually type in your password every-time you open a new tab and want to access items related to your email account. That is, unless you explicitly tell your browser to not store cookies. For convenience, we don’t mind having cookies on our browsers and not all are maliciously used against you.

Cookies are mostly used to track website activity. As you visit sites, a server gives you a cookie that acts as your ID card. When you return to sites your browser provides that cookie back to your server and this is how a web server can gather information about which sites are frequented and getting the most visits.

Servers can also use cookies to provide a personalized web experience. If you select preferences on certain sites the server can store this information in a cookie for you. Anytime you return to this webpage the server returns a page with your preferences on it.


Cookies are very useful for online shopping as well. From storing credit card information/personal information as well as any items left in your shopping cart so that you do not need to re-enter this information anytime you visit your favorite shopping sites.

Note: Accepting cookies does not give a server access to your computer or any other information that you haven’t explicitly given. It’s also not possible to execute code from a cookie, and cannot be used to deliver a virus.

Types of Cookies

Session cookies

These are also commonly known as “temporary cookies.” These types of cookies help website recognize users and information thats been provided when they navigate through the site. If the browser is closed, these cookies are then deleted (most used for shopping sites).

Permanent cookies (12 month shelf life)

Aka “Persisted cookies” can remain active even after you close your browser. These can usually be associated with login details and passwords so that users don’t have to re-enter every time they use a site.

Third-party cookies

Installed by third-parties with the goal collecting info on users for research purposes. These purposes can include spending behaviors, demographics, and many more. Many of these are used by advertisers to make sure their products are targeted at their intended audience.

Flash cookies

These are also known as “super cookies” and are independent of the web browser. These are used to be permanently stored on a users machine and much more difficult to remove.

Zombie cookies

Zombie cookies are type of flash cookie that are automatically re-created after a user has removed them. These tend to be harder to detect and manage. They have been known to have been used to install malicious software onto a users device. It’s also often used in online games to help prevent cheating.

Why are they called cookies?

“Cookie: Is a small bit of information that travels from a browser to the web server. … It was coined from the term ‘magic cookies’ that derives from a fortune cookie; a cookie with an embedded message.” — inlife



Full-Time Software Engineering Student at Flatiron School, avid golfer, and wannabe chef.

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