Browser Cookies
What are Cookies?
A cookie is a message given to a Web browser by a Web server. The browser stores the message in a text file. The message is then sent back to the server each time the browser requests a page from the server.
The main purpose of cookies is to identify users and possibly prepare customized Web pages for them. When you enter a Web site using cookies, you may be asked to fill out a form providing such information as your name and interests. This information is packaged into a cookie and sent to your Web browser which stores it for later use. The next time you go to the same Web site, your browser will send the cookie to the Web server. The server can use this information to present you with custom Web pages. So, for example, instead of seeing just a generic welcome page you might see a welcome page with your name on it.
A website can only read the cookies it has stored on your computer itself. It can not read cookies set by another website.
Are cookies bad? By themselves, No, cookies are not bad.
Cookies do not act maliciously on computer systems. They are merely text files (on windows each cookie is typically stored in its own text file, on Macintosh cookies are typically stored in a single combined file) that can be deleted at any time - they are not plug-ins nor are they programs. Cookies cannot be used to spread viruses and they cannot access your hard drive. This does not mean that cookies are not relevant to a user's privacy and anonymity on the Internet. Cookies cannot read your hard drive to find out information about you; however, any personal information that you give to a Web site, will most likely be stored in a cookie. In only this way are cookies a threat to privacy. The cookie will only contain information that you freely provide to a Web site.
The one exception we know of to the above is cookies used by some advertisers. Many websites place ads on the site as a source of revenue. If you click on a website ad, often times a cookie is placed on your computer to indicate which site you viewed their advertisement on. These cookies normally have a lifetime of about 30 days, after which they are deleted automatically. This is so the advertiser can pay the website where you saw their ad for upto the lifetime of the cookie (in case you don't purchase on your first visit).
