What is a Cookie?

A cookie is a set of data that a Web site server passes to a browser to get it stored on user's local computer, and to retrieve that information to identify you in the future. A cookie is placed on your hard drive as a tiny piece of text. Its main job is to record bits of information such as the pages you've visited items you've put into an online shopping cart, your user name and password etc.

The information stored within a cookie can be read only by the Web server that originally sent the cookie and not by other Web servers. 

Uses for Cookies

Cookies were created to maintain user information and to customize web sites. In many cases, they make it easier to navigate and use the Internet. For instance, upon your first visit to a site you are often asked to register by giving your name and a password for access to that site. The site will then place a cookie on your hard drive, which contains that information. When you return to that site, from the same PC, the cookie is retrieved and read and the web site and "recognizes" you as an authorized user. You can opt not to allow cookies by proper settings of your browser. But, if you permit cookies, you only have to register once, instead of having to enter information every time you access the site. 

What Information can a Cookie Extract?

Cookies cannot be used to get data or view data off your hard drive. Cookies do not give anyone access to your computer or any personal information about you unless you have given that information to the web site by answering questions or filling in a form. Cookies cannot give your computer a virus. That is, by allowing a web site to create a cookie does not give that site access to the rest of your computer. Only the site that created the cookie can read it again. It is similar to writing a small note in your diary for your future reference. 


Loss of Privacy

Some time cookies represent a potential loss of privacy. Cookies, by design are meant to work invisibly. They are used to track people and their activities and that makes many people uncomfortable.
Cookies can potentially be used to build detailed profiles of your interests, spending habits and lifestyle. There is a possibility that some unscrupulous group could potentially accumulate such information and sell it to companies to be used for advertising or other purposes. But, even if you don't allow cookies, it is still possible to collect your personal details to store it on the hard disc of a visiting web site server. In this case you are being recognized by your IP address. One of the reasons of creating cookies was also to save storage space on web sites hard disc. It is economical to store small pieces of personal data on millions of PC of the users rather than keeping it on web site's hard disc.

Cookies can be controlled and viewed by your Internet browser. You can also view the cookies already on your machine and decide to delete them if you think they are inappropriate or are taking up too much space of your hard disc. By changing your security preferences in your browser you can "turn cookies off". This means that no cookies can be installed on your machine automatically. This has both advantages and disadvantages in that nothing will be installed on your machine that you are unaware of, but also no "helpful information" will be recorded about you through legitimate cookies (e.g. usernames and passwords for a particular site). If you decide to disable cookies, you will have to write your username and passwords each time to login a particular site. Remember, some sites won't give you full access in case you don't permit to write cookies. 

For being faster in your work (i.e. mainly dependent on surfing sites) you should enable cookies so that every time you open a site from your PC, you are not asked to enter your username and password.