Cookie Clarity

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What is an HTTP cookie?

A piece of data from a website that is stored on your computer while you visit the site.

Who needs it?


  • To remember your log-in info, so you don’t have to sign in each time.
  • To keep items in your cart so you don’t lose your stuff while you browse.
  • To remember which videos you watched so you don’t waste time.

Site owners

  • To deliver targeted ads based on user browsing activity and queries.
  • To track unique visitors to collect web traffic data (i.e., how many people are visiting, how long are they staying, how often do they return?).
  • To understand users and offer curated suggestions (Amazon — similar products, Youtube — relevant videos).

How does it work?

  • The first time you visit a site, the site gives you a cookie with your own unique identification number (think number of chocolate chips) which sits on your hard-drive (jar).
  • This ID keeps track of your visit, what you click, view and stream.
  • An HTTP cookie is specific to one website and cannot track your activity on other sites (see third-party cookies below).

When did it start?

  • Invented in 1994 by a 24 year old Netscape programmer, Lou Montulli II.
  • A client complained that their servers were being overloaded from storing the cart data of each visitor as they browsed.
  • Lou needed a way to store each user’s cart data on their own computer to save server space and hosting costs for the client.
  • Lu took the existing magic cookie concept and restructured it for web browsing which is what is used today.

Why are they called cookies?

The magic cookie is a computing token from 1979 that would verify and track users on a system by passing a crumb of data between the server and the user’s computer

But what about third-party cookies?

If you are browsing a website that has a button to like or share to another site, that third-party site can now send their own cookies to the original website to track your activity and serve you targeted ads.


Cookies are used to identify users and track activity. Do you find them helpful or a breach of privacy? IMO, it depends on how the website decides to use the information. It can create an enjoyable user experience and save time or bombard my feed with products I already own.




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Bella Rubin

Bella Rubin

Translating tech into English.

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