Aug 22nd 2011
NO FEELING makes chills run more feverishly up and down a spine than the sense that its owner is being watched. People whose spines tingle a bit too often are typically branded as paranoid. Go on the web, however, and your spine ought reasonably to go into crisis mode. Internet users are indeed being tracked all the time. And shaking off a virtual tail can be tough.The reason is a tiny chunk of text called a cookie. It is inserted by websites into a browser to help them identify a user as he loads pages in succession, or returns on subsequent visits. They come with an expiration date, which can be minutes or years ahead, after which the browser deletes them.
Cookies are a staple on sites which require users to log in, allowing for a continuous session after a single authentication. They may also be used to store preferences without an account, such as text-viewing size. Millions of sites use cookies for analytics; they permit a user's page requests to be divided into sessions and then aggregated into visitor counts and other metrics that tell a site's owners what people are reading, where they come from and how they move about. Cookies have a more directly commercial purpose, too. They are used to track behaviour, and so target advertising. Cookies let marketers pinpoint the sorts of offers likely to attract a particular user. That lets sites demand higher fees for virtual hoardings.
Continue reading ....
No comments:
Post a Comment