Understanding cookies

A cookie is a file created by an Internet site to store information on your computer, such as your preferences when visiting that site. For example, if you inquire about a flight schedule at an airline's Web site, the site might create a cookie that contains your itinerary. Or it might only contain a record of the pages you looked at within the site you visited, to help the site customize the view for you the next time you visit.

Cookies can also store personally identifiable information. Personally identifiable information is information that can be used to identify or contact you, such as your name, e-mail address, home or work address, or telephone number. However, a Web site only has access to the personally identifiable information that you provide. For example, a Web site cannot determine your e-mail name unless you provide it. Also, a Web site cannot gain access to other information on your computer.

Once a cookie is saved on your computer, only the Web site that created the cookie can read it.

A persistent cookie is one stored as a file on your computer, and it remains there when you close your browser. The cookie can be read by the Web site that created it when you visit that site again.

A temporary or session cookie is stored only for your current browsing session, and is deleted from your computer when you close your browser.

A first-party cookie either originates on or is sent to the Web site you are currently viewing. These cookies are commonly used to store information, such as your preferences when visiting that site.

A third-party cookie either originates on or is sent to a Web site different from the one you are currently viewing. Third-party Web sites usually provide some content on the Web site you are viewing. For example, many sites use advertising from third-party Web sites and those third-party Web sites may use cookies. A common use for this type of cookie is to track your Web page use for advertising or other marketing purposes. Third-party cookies can either be persistent or temporary.

Unsatisfactory cookies are cookies that might allow access to personally identifiable information that could be used for a secondary purpose without your consent.

Most Browsers allow the use of cookies; however, you can change your privacy settings to specify that your browser prompts you before placing a cookie on your computer (this enables you to allow or block the cookie); or you can prevent your browser from accepting any cookies.