Computers & Internet: how much does your computer tell others about you

Computers & Internet: how much does your computer tell others about you

Have you ever had the feeling your computer is watching you? That somehow it knows what you were looking at yesterday, or last year?

And that rather than being your technological ‘friend’ it behaves more like a slick second-hand car salesman?

You fancied flying to Paris so you checked out airfares . . . and before you knew it, your Facebook page was plastered with advertisements for hotels on La Rive Gauche.

Your daughter bought a record by One Direction. Now, the family computer is bombarded with ads for boy band concerts.

It is all because of something on your computer called a ‘cookie’. The origins of their name are unclear, but cookies are vital to the running of the internet.

When you visit a website, that site places a unique cookie on your computer so it recognises you when you come back. It allows the website to remember your login details and other pieces of information to save you entering them again and again.

If, say, the site offered up weather information, it might remember that you were interested in conditions over a particular town, and so on.

These devices — known as ‘first party cookies’ because they involve an exchange of information only between you and the site — make shopping on the internet possible.

If you shop for groceries over the internet, for example, cookies allow you to update your shopping trolley day after day, returning as you remember to add new products before moving to the virtual checkout at the end of the week.

And cookies can remember your credit card details to save you having to enter them over and over again. So far, so good.

Problems arise when advertisers get involved. You may think all the websites you visit as you use the net are free, but they aren’t.

In return for using them you automatically part with slices of information about yourself that can be used to send advertisements to the pages you look at as you surf.

This happens because of ‘third-party’ or ‘tracking’ cookies. These are placed on your computer by companies who profit from finding out what interests you or what — from your searches — you are looking to buy.

During one 15-minute surfing period, one investigator’s computer was inundated with 600 cookies, 350 of which were the tracking variety.

Read more: http://www.dailymail.co.uk/sciencetech/article-2277265/Your-watching-How-sinister-cookies-track-online.html#ixzz2KhpEpu5P