Newsletter

Geek Speak: Cookies

By Mike Takashino, Testing & Quality Assurance Officer

What is a cookie?

A cookie is a little packet of information stored on a user’s computer by a web server. Websites that use cookies will drop one on your computer every time you view a web page; and they read the cookie back every time you request another page from that site.

There is a good logic for this. The Internet system for delivering web pages (hyper-text transfer protocol – HTTP) is stateless. That is, your link to a website exists only momentarily while the page you request is being delivered. Once you have received the page and all its content, the connection between your computer and the website is broken. On your next page request, the server has to re-establish who you are. The cookie aids this process.

Note that a cookie is a very small text file – there is a limit on the number of characters that it can store. A cookie is not a program. It can’t view, change anything or damage your computer, and it can’t tell the web server anything the server didn’t already know (ie, the server gets back only what it put in the cookie in the first place). Moreover, a web server cannot read cookies left by another website.

Why are they called cookies?

The name "cookie" was derived from UNIX* objects called magic cookies. The magic cookies are essentially tokens that are attached to a user or to a program and change depending on the areas entered by the user or the program.

* UNIX is an operating system that was developed at Bell Labs back in 1970’s. It is robust and fast and is used extensively, especially for mission critical operations. (It forms the basis for the Linux operating system.)

What do cookies do for me?

Cookies can save you time and give you instant access to customized information on the Internet. This is because they can allow a website to "recognize" you and remember information that you have given to the website previously. For example, Yahoo, Amazon, and CNN use cookies to save your log-in information on your computer, remember what’s in your shopping cart, or customize their pages to match your preferences.

Do cookies invade my privacy?

Not really. They can help web site managers to track your path through their websites and build up a more complete picture about you as a user. If you fill in a form such a site, that information can used to enhance the cookie records. And the paranoid among us worry about website owners sharing this information. But generally, the motives are to make your viewing experience richer. Overall, cookies are beneficial to us as surfers and you can make your browsing more difficult if you disable cookies.

Cyber-dynamics and cookies

By the way, when we deploy cookies we usually encrypt the data to provide a greater measure of privacy – to prevent anyone at your keyboard from reading what we store.

What do we use cookies for? Well, for example, if you are referred to a website for one of the insurance companies that we work with, we store the referring broker’s reference number (if any) in a cookie. Then, if you buy an insurance policy online from our client’s website, your application includes the broker’s reference number so that the insurance company can say thank you or whatever. It’s similar to applying using a pre-printed form with the reference number on it already.

We also have log in systems were we ask the user if they want to save the log in information on their computer to speed up their next visit. If they say yes, we store the data in an encrypted cookie. And, of course, we use cookies for shopping carts, online quiz games and other systems where we have to remember information between page requests. But rest assured its all harmless.

So where are the cookies?

Okay, so now you are wondering where the cookies are on you computer... all of the cookies are stored in a folder on your hard-disk. If you are using Windows, you can find the cookies in the Temporary Internet Files folder on your hard-disk.

You can view the cookies through Microsoft Internet Explorer (IE) 5 or 6 by doing the following:

On your IE task bar, click:

1. Tools, then
2. Internet Options.
3. Under the tab General (the default tab) click
4. Settings, then
5. View Files.

Netscape 7.x users can manage and delete cookies by clicking "Tools" and then "Cookie Manager".

If you are using older versions of Netscape you can do the following:

On your task bar, click:

1. Edit...
2. Preferences...
3. Then click on the grey arrow next to "Advanced" so that it is pointing downwards
4. Select Cookies
5. View Stored Cookies.

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