Definition: P3P

(Platform for Privacy Preferences) A protocol for sharing private information over the Internet from the World Wide Web Consortium (W3C). A website's privacy policy is defined by the Webmaster answering a standard set of multiple-choice questions, which result in tags embedded in the website's home page. Users also define their privacy requirements in their P3P-enabled browsers; for example, whether they allow their names disclosed to third parties. If the website policy and user preferences are not the same, the browser alerts the user.

Automatic Disclosure
P3P also assists with online sales. It lets users decide what data they are willing to divulge automatically to the site, such as shipping address and credit card number. If the site requests more data, the browser alerts the user, who can then decide whether to share it or not.