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What are cookies?

A plate of cookies

If you’ve ever read a newspaper article about the internet, it’s likely that someone, somewhere will have mentioned ‘cookies’. They may have been explained as an evil and intrusive spying mechanism tracking your every move on the net - or a harmless device designed to make your life easier. This guide should clear up any confusion and ease any concerns.

Jane Fae | 9th September 2010

First, and contrary to popular belief, cookies are NOT programs. They don’t do anything at all. They are simple ’text files’ which you can read using the Notebook program on your own PC. Typically, they contain two pieces of information: a site name and unique user ID.

How do they work?

When you visit a site that uses cookies for the first time, a cookie is downloaded onto your PC. The next time you visit that site, your PC checks to see if it has a cookie that is relevant (that is, one containing the site name) and sends the information contained in that cookie back to the site.

The site then ’knows’ that you have been there before, and in some cases, tailors what pops up on screen to take account of that fact. For instance, it can be helpful to vary content according to whether this is your first ever visit to a site – or your 71st.

The good thing about cookies…

Some cookies are more sophisticated. They might record how long you spend on each page on a site, what links you click, even your preferences for page layouts and colour schemes. They can also be used to store data on what is in your ’shopping cart’, adding items as you click.

The possibilities are endless, and generally the role of cookies is beneficial, making your interaction with frequently-visited sites smoother - for no extra effort on your part. Without cookies, online shopping would be much harder.

…and the bad

So why the paranoia? The answer probably depends on how you feel about organisations – both big business and government – storing information about you. There is nothing especially secret or exceptional about the information gathered by cookies, but you may just dislike the idea of your name being added to marketing lists, or your information being used to target you for special offers. That is your right, just as others are entitled to go along with the process.

When cookies first started to appear, there was controversy. Some people regarded them as inherently sneaky - your PC was being used (without warning) to store personal information about you, which could then be used to build a picture of your browsing habits.

Control your cookies

If that was really what was going on, you would definitely have grounds for objecting. In reality, the collection and storage of personal information without permission is not strictly legal in the UK. Sites that make use of cookies get around this in two ways.

Firstly, if you read the small print in the Terms and Conditions, you will almost certainly find that by using a site, you are agreeing to download the site cookies.

And, if that still feels a bit more invasive, almost all web browsers nowadays allow you the option to block cookies. That means you can block all cookies or, with a little more effort, you can start to pick and choose which ones to accept.

It makes browsing a little clunkier - some sites do not work with the cookie-option turned off. However, if it really matters to you, then that option is always available.


Jane Fae

Jane Fae

Jane is a consultant on database marketing and crm, as well as a nationally known writer on issues of political and sexual liberty. She also writes for the Register, one of the world's biggest online tech publications, about current affairs, policing and the law as it impinges on technology users.

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