Is it Okay to Delete Cookies?

"Cookie" is a term used for information sent over the Internet and stored on a user's computer. Cookies are used to let a website know who is accessing the site. Cookies store information such as user logins, shopping cart contents, user preferences for a website or other user information. Without cookies, many websites would be unavailable or unable to function properly. Online shopping carts would be unable to remember which items a person added to their cart, and password-protected sites would be unable to recognize a repeat visitor without that visitor having to type in their login information each time.

Deleting cookies deletes all of this stored information. At times, it may be useful to delete cookies to remove bugs in websites and/or excessive data on computer hard drives. However, users should be aware of the effects of deleting cookies prior to taking this step.

What Is a Cookie?

A "cookie" refers to a small string of text code placed on a user's hard drive by a website or web browser. Cookies are also called "tracking cookies," "browser cookies," "computer cookies," "Internet cookies," "HTTP cookies" and "web cookies."

Contrary to popular belief, it is not a program that runs off the web user's computer, nor is it spyware or a virus (although some tracking cookies may be identified by anti-spyware products as spyware).

Cookies are sent in HTTP form by a website—or web server—to a web client (the person using the web). Generally, the individual web browser is the web client. For example, a website would send a cookie in the form of an HTML header to Firefox, Safari or Internet Explorer.

The cookie contains one or more name-value pairs, each with bits of information that a website can recognize. The information may include user preferences for the website, login information, shopping cart contents, identifiers for server-based sessions or any other data that a website needs to recognize a user and the user's previous actions. Cookies can also be used by websites for website maintenance or tracking visitors to their sites.

After a website places a cookie on a web browser, that cookie is sent back to the website each time a client directs his browser to that particular website. Thus, the repeat visitor will be greeted with a shopping cart that contains items he added previously, or a specific web experience that matches previously selected preferences. The website will recognize that this user has been there before, because of the cookie, and act accordingly.

What Happens if I Reject Cookies?

Most web browsers allow users to set their preference to reject cookies. However, rejecting cookies makes some websites unavailable or non-functional. A website that requires a user to be logged in to access features will not work without cookies, since the website will not receive the "cookie" allowing them to recognize the visitor as being logged in.

Websites that use shopping carts also will not function properly without cookies enabled, since that website will be unable to recognize or remember what items the user added to their cart without a cookie to give them that data.

What Happens if I Delete Cookies?

If you delete cookies, the entire history of your web browsing experience will be lost. Any websites that you were logged into or set preferences for will not recognize you. You will need to log in again and reset all of your preferences. Any items you had stored in a shopping cart on any website will no longer be there. You will need to add those items again. When you add the items again and/or login again, new cookies will be created.

When Should I Delete Cookies?

You should delete cookies if you no longer want the computer to remember your Internet browsing history. If you are on a public computer, you should delete cookies when you have finished browsing so later users will not have your data sent to websites when they use the browser.

If you are on a private computer, you will want to delete cookies if and when you no longer want that computer to remember your Internet preferences. You can do this to protect your privacy—if you don't want others to see sites you have logged into or things you have added to your shopping cart(s). You can also do this if websites stop acting properly, in order to reset the website and have the site see you as a new user.

How Do I Delete Cookies?

How to delete cookies varies from browser to browser. Firefox allows users to delete cookies by going to the Preferences Menu. Once you have selected "Preferences," go to the Privacy Tab and select the "Show Cookie" option. You then have the option to highlight a specific cookie and delete that cookie or to remove all cookies.

In Safari, the option to delete cookies is also under the Preferences menu option, but in Safari, the subtab is called "Security." Again, you can delete individual cookies or all cookies, depending on your preference. Internet Explorer also allows you to delete cookies by going to the Preferences menu, and there is an option within that menu entitled "Cookies." You can also set your browser to automatically delete cookies after a certain number of days.