Platform for Privacy Preferences (P3P)

Platform for Privacy Preferences (P3P) is a protocol that has been developed by the World Wide Web Consortium (W3C) that allows Web sites to declare to users its intended use for the information it collects.

Companies are storing more and more information about their users to determine demographic information and buying habits and to provide specifically targeted advertisements. Some Web sites, however, use controversial practices like tracking cookies to keep track of the user, and then send advertisements to them.

Most people see tracking cookies as an invasion of their privacy. P3P gives users more control over what kind of information they wish to release to Web sites.

To be P3P-compliant, Web sites must declare the information they collect and what they intend to do with it in a privacy policy. The link to a Web site's privacy policy can usually be found in the footer of the homepage.

A typical privacy policy contains three main sections:

• Type of information stored
• Machine information like IP address, etc.
• User information like name, password, and other demographic information
• Whether the user has a choice about the nature and amount of information being stored
• Use of this information
• Use for advertisement, tracking, etc.
• Whether this information will be sold to other Web sites, or provided to other “friendly” Web sites
• Duration of storage
• How long this information will be stored

A browser plug-in called Privacy Bird  is a free tool that understands privacy policies from Web sites and presents it to the user in easy-to-understand format. When the user visits a Web site, it displays a green bird for sites whose policies match the preferences of the user, and a red bird for those that do not.