COOKIES – they are basically small text files (up to 4KB). They are created by websites that you have visited.

They are stored within your computer's operating system, either temporarily or permanently on the hard drive.

They have an important role - they allow websites to recognise and record your preferences. Whenever you access a website, cookies will allow you to remember logins and passwords, your favourite settings, customised contents, etc.

Their location depends on the browser. Any time you visit a website, your browser passes a relevant cookie back to the server.

That way a web server can gather information about which web pages are used the most, and which pages are visited repeatedly. This is particularly useful if you often do online shopping.

Cookies contain various URLs (or simply website addresses) to which they refer to. If you enabled them on your computer, you can see them at work whenever you are logging into your email account or some website that requires login and password.

User hashes of logins and passwords are stored in a cookie, which also enables your unique user ID, so you don’t have to type in the same information all over again when accessing a particular website.

Websites mainly use cookies to:

  • identify visitors and users
  • remember users’ custom settings
  • help users complete tasks without having to re‑enter information when visiting the website again




Computer cookies (just like the traditional baked ones!) can have a certain life expectancy.

Based on that, we can divide them into 2 groups:

  • session – these are erased when the user closes the browser, ending a browsing session.
  • persistent – these can stay on the user’s device for a period of time, even long after a browsing session was finished.

Furthermore, they can be classed as below:

  • first-party – these are set by the web server of the visited page. They are necessary to keep track of your personal preferences and the current browsing session
  • third-party – these are set and stored by websites different to the one you could be currently browsing. The third party cookies are often gathered and stored by third-party advertisers. The purpose of these is usually to track your Internet surfing habits. The third-party types are commonly considered an invasion of privacy.




The European Commission issued clear instruction on cookies and gathering of personal information. It gives the following guidelines to online service providers and website administrators:

"You must ask users if they agree to most cookies and similar technologies (e.g. web beacons, Flash cookies, etc.) before the site starts to use them. For consent to be valid, it must be informed, specific, freely given and must constitute a real indication of the individual’s wishes.”

It is important to remember that certain types are exempt from the above requirement.

These include (quoting after the European Commission’s website) the following cookies:

  • user‑input (session-id) such as first‑party cookies to keep track of the user’s input when filling online forms, shopping carts, etc., for the duration of a session or persistent cookies limited to a few hours in some cases

  • authentication, to identify the user once he has logged in, for the time of a session

  • user‑centric security, used to detect authentication abuses, for a limited persistent duration

  • multimedia content player, used to store technical data to play back video or audio content, for the duration of a session

  • load‑balancing, again during a session

  • user‑interface customisation, such as language or font preferences, for the duration of a session (or slightly longer)

  • third‑party social plug‑in content‑sharing cookies, for logged‑in members of a social network.




As explained above, cookies can be very helpful and save you a lot of time, especially when you are utilising a large number of websites and you want them to remember you preferences, settings, or simply to keep you logged in to your account.

Sometimes, however, deleting them can be necessary.

Why and when should you delete them:

  • If your computer stores a very large number of cookies – this can affect it’s performance, especially if it’s an older machine.
  • If suddenly you notice personalised ads from other websites which seem to suggest that somebody knows what content you have been browsing - this means tracking cookies have been gathering information about what stuff you browse and have been adjusting online ads for that content.
  • If you visit sites you don’t want others to know. By deleting cookies you can eradicate proof of ever visiting such websites on your browser.




Instructions on how to delete cookies can vary depending on the browser you are using:

Google Chrome:

Google Chrome cookiesCredit: Safety Online Info


Internet Explorer:

IE cookiesCredit: Safety Online Info

Apple Safari:


Apple safari cookiesCredit: Safety Online Info