Cookies: the little biscuits of the Internet that remember our visits

By Gianluca Bonomo — Technology Trainer and Instructor

Published on October 20, 2026

You open a site to read the news or buy a pair of shoes and, before you even start, the usual question pops up: «Accept cookies?». Most of us click without thinking. But what did we just accept?

In this lesson you find out what cookies are, who keeps them, which ones are useful and which ones seem to remember the shoes you looked at yesterday a little too well. No computer expertise needed.

1. Biscuits by name, reminders in practice

The first time you read «Accept cookies?» you think: if they are chocolate chip, gladly! Then you find out nobody is bringing you a tray.

In computing the name comes from magic cookie, an expression for a small packet of data that a program receives and then hands back. The biscuit reference is there, but it was not meant to lure customers with something tasty: that is, if anything, a funny metaphor for some advertising uses.

A cookie is a small piece of information that a website asks your browser to keep. The browser is the program you surf with: Chrome, Firefox, Safari, Edge.

When you come back, the browser hands the note over and the site recognises something about your earlier visit. Often the cookie holds just a code: the details of the basket or the account stay on the service's servers. So not all your activity is written inside your device.

2. A quick refresher: browser and search engine

To understand who keeps the notes you need a distinction that confuses half the world. The browser is the car you drive along the roads of the Internet. The search engine is the map that helps you find your destination.

Chrome is a browser; Google is a search engine. You can open Chrome and use Google to look for a pastry shop, or type the shop's address directly. Cookies are handled by the browser, that is, the car.

3. How they work: let's go shopping

You enter an online shop and put a box of chocolates in the basket. Then you move to another page to pick a second item. The site has to remember that basket belongs to your visit: a cookie can help it do that.

Without a way to link the pages of your visit, it would be like reaching the till and hearing: «Have we met before? And whose chocolates are these?».

Other cookies keep you signed in to your account or remember a preference, like the language. They do not all last the same.

Some live only for the browsing session; others have an expiry date and may stay longer. Whether your basket survives closing the browser depends on how the site is built.

4. Not all cookies do the same job

To keep things clear, picture three characters.

• The organised shop assistant uses technical cookies: keeps track of your basket or your sign-in session.
• The counter at the entrance uses statistical cookies: helps work out how many people come in and which pages they read.
• The salesman who remembers your tastes uses profiling cookies and other tracking tools: can build a profile of your interests and show you personalised ads.

It is the last ones that seem to whisper: «You looked at those shoes… want another look?». Technical cookies mostly do practical work. As for statistical ones, whether consent is needed depends on how they are used.

5. Why do the chocolates seem to follow us?

You search for a box of chocolates. You look at a few products, compare prices, then go and read an online newspaper. Later an ad for chocolates shows up. Coincidence?

Sometimes yes. Other times advertising tools that link visits through a browser identifier may have played a part. This is where third-party cookies come in: those belonging to a service other than the site you are visiting, for example an ad service present on many sites.

To tell them apart, always ask yourself who placed the cookie.

6. The banner is not the cookie

The window with «Accept», «Reject» and «Customise» buttons is called a cookie banner. The cookie is the stored information; the banner is the interface through which the site informs you and, when needed, asks for consent.

In Italy and the European Union, technical cookies needed for the service do not require prior consent, while profiling cookies do. A site using only technical cookies can therefore inform you without asking you to accept everything. (In Italy the rules are explained by the Garante, the Data Protection Authority.)

6.1 What happens if you refuse

Refusing advertising cookies does not switch off the basket: that can work with technical cookies. Blocking every cookie from the browser settings, instead, can break some features. And accepting a banner is not a blank cheque to use any of your personal data.

7. Cookies, cache and history: three different drawers

While you browse, the browser keeps several kinds of data. Mixing them up is easy, but they do different jobs.

The browser does not use the cache out of laziness: it follows rules to decide when it can reuse a file and when it must check whether it changed. Sometimes, though, an old version of an element appears. Refreshing the page may be enough; in some cases you need to clear the cache.

8. Cleaning the browser: what to expect

In the browser settings look for the privacy section or the one for clearing browsing data. Before you confirm, check which categories you ticked.

• Clear cookies: you may be signed out of accounts and lose some preferences.
• Clear the cache: some pages will take a little longer on the first load.
• Clear the download history: the downloaded files usually stay where they are.

The space you free up varies: cookies weigh little, the cache can be bigger. And cleaning the browser does not delete the data services have already stored on their own servers.

Many browsers also let you limit third-party cookies: a useful choice to reduce some forms of tracking, although it may cause trouble for certain services embedded in sites.

9. Next time «Accept cookies?» appears

Stop for a moment and read. Do you need only the cookies necessary to use the service? Do you want personalised ads too? Would you rather pick the categories?

You do not have to accept everything in a hurry, nor treat every cookie as a suspicious guest. Just understand what job it does.

It is like being offered a tray of biscuits: knowing what is inside helps you choose. And on the Internet, at least, reading the label will not let your tea go cold.

Hands-on exercise

Ten minutes, your everyday browser and a site where you often shop or sign in.

1. Open the site and look at the banner: which buttons are there? Is there a «Customise» one?
2. Click «Customise» and note which categories you find (technical, statistical, advertising).
3. In the browser settings find the privacy section and see where cookies are managed.
4. Find the screen to clear browsing data and read the categories without confirming: can you say which drawer each one matches?
5. Write three lines, in your own words, on the difference between cookies, cache and history.

Questions that come up in class

Glossary

Further reading

• Garante per la protezione dei dati personali (Italian Data Protection Authority), cookie FAQ — https://www.garanteprivacy.it/faq/Cookie
• Garante, guidelines on cookies and other tracking tools, summary sheet — managing preferences and consent
• MDN Web Docs, Using HTTP cookies — https://developer.mozilla.org/en-US/docs/Web/HTTP/Guides/Cookies
• MDN Web Docs, HTTP caching — https://developer.mozilla.org/en-US/docs/Web/HTTP/Guides/Caching
• Wikipedia, HTTP cookie — origin of the term, from magic cookie