When you connect or login to a website with your Facebook account, it can access information you’ve added on Facebook in order to provide a social and personalized experience on the site. The Facebook Platform Policies restrict how these sites can access and use this information.

This means that if you’ve blocked a user on Facebook, that user will not be able to see you on a "connected" site. When other users connect with a website, those users will not be able to see information you’ve added through Facebook that they wouldn’t otherwise be able to see simply by browsing Facebook. You can decide what types of information your friends’ apps can access from the "Apps and Websites" section on the Privacy Settings page.

You can use your Facebook account on several third-party websites and apps. These websites and apps are using the Facebook Platform. Look for the registration tool or a Login/Connect button that prompts you to login with Facebook. You should make sure that clicking on the Login/Connect button opens in a separate browser pop-up window, and that the Web address (URL) for the pop-up contains the proper "www.facebook.com" domain. If it does, you’ll know that it’s a legitimate Facebook page and not a phishing attempt, and you can log in safely and securely.

Just as News Feed has always enabled you to see what your friends are up to on Facebook, now, depending on the privacy settings of everyone involved, people can share many of the actions they take on the rest of the Web as well. People always have the option to refuse a News Feed story from another site. We want to give you the stories we think you’ll find most interesting and relevant; by including the actions you and your friends take both on and off of Facebook, we believe we will make News Feed even better at helping you stay in touch with your friends.

Facebook cannot track your actions on external sites unless you decide to connect your Facebook account to that site and/or explicitly decide to publish a story to your Wall (timeline) via the Like button. For example, if you are on Digg, and digg an article or comment on an article, Facebook will only be notified of the actions for which Digg wants to create a story. Facebook will have no access to other actions you have taken or other information involving your Digg account. To take advantage of the ability to generate stories from another site, you must "connect" your Facebook account to that site, or otherwise be logged into Facebook while you interact with one of these sites.

Facebook is available on over a million websites, devices and apps, including Rotten Tomatoes, Bing, Scribd, CNN, Pandora, CBS.com, Yelp, YouTube, Xbox, and Nintendo DSI. If you can’t find Facebook on your favorite sites, contact the website administrators and make the suggestion that they implement the service!

When you "connect" your Facebook account to your account on another site, you can automatically see which friends of yours have already connected their accounts, and they can see you as well.

When your friend connects their Facebook account with an external site, they will be able to compare their Facebook Friend List with information from that website in order to invite more friends to connect. For example, if you use Digg.com with the same email info as your Facebook account, and your friend connects their account with Digg, they will be able to see the fact that you have a Digg account unless you check the box discussed below.

You can opt-out of being found on other sites by selecting "Turn off Platform" here.

Please read the details here.

The form operates as an iFrame, hosted by Facebook. The tool takes the information that you’ve previously entered on Facebook and pre-populates the form for your convenience. Only you can see this form, and the information won’t be shared with the website until you explicitly click "Register". Until you click "register" the form functions as an iFrame, and no pre-filled data is shared.

The website will only get information you choose to share with it. Any information being requested will be clearly shown to you so you can decide to share the information to register for the site or not.

The website may also ask for custom fields, such as your favorite football team, which you can choose to share or not to share. If you choose to share custom information, that information passes through Facebook (but is not stored on Facebook), and will only be used for the website’s sign up flow.

You will not see a prompt for the permissions dialog.

No, you cannot opt out of showing up on the facepile after registering with the site. You can, however, uninstall the app by going to their app privacy settings. By uninstalling the app, you will will not show up in the facepile.

Extended permissions for profile (timeline) information are displayed on the form (ex: birthday, email). This was a design decision to provide more data transparency to the information that you are passing to the site.

This is not instant personalization since no information is shared with the site before you click Register. This is not a social plugin because it gives you the ability to share your Facebook information with the site. The form does not result in any type of publishing back to Facebook.

The site is notified that you have decided to end a connection and should not show you your friends. However, you must go to the website to delete your account on the site.

No, the form does not result in any type of publishing back to Facebook, and Facebook does not store any data without explicit permission from the user (a checkbox will appear in your basic info fields like birthday).

If birthday is set to the "only me" privacy setting, it will still be pre-populated on the tool because it is being viewed by you. No information is shared with the site until you click "Register."