Cookies - What are they and why should you care

Cookies are small pieces of text which are stored in your computer as you visit web sites.  A web site will place a cookie into your machine to help the website recognize you .

The Good Side...

This can be very useful (and necessary) when customizing a web site or accumulating items in a shopping basket. Without cookies, a  web site would have to treat every single person as a "stranger", and would be unable to present a user with personalized content.  For example, if I choose to be an ongoing customer of Amazon.com, I consider it "pretty good marketing/customer service" that they can:

• greet me by name
• suggest new items which I should be interested in based on previous purchases
• Remember the 3 items I've  placed into my shopping cart as I continue to explore their web site. Otherwise I would have to write down all the item numbers, and then enter all the information on one long order form when I am ready to buy.
• When I am ready to buy, I can simply enter a password instead of re-entering all my credit card and mailing list information

Amazon is able to provide these feature by writing and reading a line of text (cookie) on my machine that contains not much more information than: "amazon.com customer ID=some_long_unique_number"

The Bad Side...

The greatest concern with cookies is when they come from third party web sites.   For example and advertising company may handle the advertising banners you see displayed on hundreds of different web sites.  As you visit a web page, the advertisement banner (And its own cookie) may be downloaded from the ad_company's server.   It is possible for a major company such as doubleclick to develop an extremely detailed profile of your web surfing patterns including which sites you have visited, what key words have you searched for, etc. Imagine if they tell (sell) to the insurance companies the names  of medical sites/conditions that were being researched by every web surfer.

Cookies are stored in your computer in the following standard locations:

• Netscape - C/program file/Netscape/users/your_user_name/cookies.txt
• MS Explorer C/windows/cookies
• OR just search for the word cookies in your computer

The cookie files can be read using any standard text processor

A well-written cookie will contain only obscure user IDs that make sense only to the web site that reads/write that cookie.  A poorly written cookie will contain your real name, real email address etc.  Also a word or caution, you may discover domain names in your cookies which suggest that your computer was used to visit "adult_only sites"  Your computer may or may not have actually visited such sites.   Many such cookies can be placed into your machine from the advertising banners from an "accidental page"  For example if a family member accidentally went to whitehouse.com instead of whitehouse.gov, they may have received many cookies from pornography banners.  (I just want to make sure I don't accidentally cause any divorces based on sneaky cookies being discovered in your computer)

Web bugs - also cause many cookies.

• FAQ about web bugs.
• bugnosis - tracks and displays hidden web bugs on web pages while you surf.
  

• Cookie Central - A comprehensive site that educates and provides links to tools.
• Cookies info from EPIC.
• How Internet Cookies Work - how stuff works - great explanation and actually shows you your cookie at their site - and how it is collecting information about your movement there.
• An example Ad Tracking set of sites created by privacy.net
• RFC 2965 - the Internet's technical standard for cookies.
• idcide - one of many applications that let you manage your cookies
• Many other cookie tools are available at my getting software resources.
• Doubleclick Privacy  - Opt Out - Double click advertising banners are tracking almost your every move - go to this page now and click on the "opt out here button"

Note for my Alumni: Your referrals are always appreciated