SAN FRANCISCO, California — Facebook is launching a new suite of tools that bring the Facebook social experience to any site on the web.

The company is releasing a set of products called Social Plugins, which any web publishers can drop into their website using one very simple line of code. These plug-ins will let visitors “Like” news stories, photos and so on. Once a user likes something, it instantly gets added to the appropriate section of their Facebook profile.

The plug-ins are part of a new Facebook initiative to make every website on the internet sharable across its network, something the company is calling the Open Graph.

The announcements were made by Facebook CEO Mark Zuckerberg and platform engineer Brett Taylor at the company’s F8 developer’s conference taking place here Wednesday.

Facebook will roll out the Like buttons Wednesday morning, and Zuckerberg boldly estimates that within 24 hours, there will be one billion Like buttons across the web.

Facebook has often been branded as the next AOL, a website that basically recreates several experiences available on the open web — chat, e-mail and link sharing — behind a closed gate. But with Wednesday’s Open Graph announcements, the company is giving website owners a bigger door into Facebook’s closed system using simple HTML tools and by incorporating open standards into its authentication system.

Zuckerberg, speaking with his trademark brand of stiff, awkward enthusiasm, calls the new Open Graph initiative “the most transformative thing we’ve ever done for the web.”

A grand platitude, certainly, but one of the most transformative shifts in Facebook’s policies, as it enables sites to more easily link up their content on the open web with the Facebook ecosystem and access its 400 million active users.

“With these tools, any web page can become a Facebook page,” Taylor says. “If you don’t like the way Facebook pages look, just make your own. Add the Like buttons and the Open Graph elements and you’ve got a page that’s fully integrated into Facebook.”

Central to the experience is the Like button. Websites can add them by dropping in an i-frame, and when a Facebook user clicks on it, it’s the same as them clicking on a Like button inside Facebook. Facebook knows who the person is, because it can now see a user’s logged-in state via a cookie.

There’s also a Recommendations plug-in, which shows you a curated list of content on the site you’re visiting that you might be interested in.

It’s not just a blind list of the 10 most-read or most-e-mailed articles on the site, Taylor explained, but a socially curated list based on what you are interested in.

Third is an Activity Stream plug-in, which shows you what your friends are up to and Liking around the web.

The new social plug-ins offer instant personalization to any website, Zuckerberg says. “You can have a user who’s never been to your site before and present them with a totally personalized experience.”

The final widget is a Facebook Bar, a toolbar website publishers can float at the bottom of their site’s user interface (again with an i-frame) to make these sharing features more visible. It also has elements that let users send Facebook mails or hold chat sessions.

To handle user authentication across all of these pieces on the web, Facebook is adopting the OAuth 2.0 standard — an open-source industry standard that’s already being used by Twitter and other social networks. We expected something like this and predicted it in our pre-conference coverage.

During a press conference after the keynote, Zuckerberg and Taylor said that Facebook will be ditching the Facebook Connect brand. Connect will be replaced by OAuth 2.0, and all authentication will be handled by the various Open Graph tools, which utilize the standard.

“It’s an industry standard and it’s super easy,” Taylor said of OAuth, “You can implement it in about five minutes, as opposed to five days for our old authentication system.”

Facebook is also giving websites a new way to identify themselves using semantic HTML. The new markup tells Facebook what type of real-world object your site represents. So, if you run a band website, you can add semantic HTML tags that tell Facebook a bit about the band: we are called Throbbing Monkeys and we are from San Francisco. So, when a Facebook user clicks on the Like button embedded on your page, the band gets added to the “Music” section of their profile.

Best of all, the link that appears on the user’s Facebook profile will lead directly to the website where the Like button was clicked — a first.

“For the first time, the Likes and Favorites on my profile page are linked to sites off of Facebook.com,” Bret Taylor said. He earned a round of applause.

Finally, Faceboook is also dropping the policy that forbids outside applications from holding on to user data for more than 24 hours. This was a controversial policy to begin with, since it prevented developers from making anything (like an RSS reader or a photo-browsing app) that let the user keep things like status updates any longer than a day.

“This is just a technical restriction that we’re lifting,” Taylor says. “It doesn’t change any of the rules around what you can and can’t do with the user data.”

Facebook is offering real-time user action updates as part of the new Graph API, which makes it easier for developers to consume user’s activity streams.

Brett Taylor, who walked through the real-time features of the Graph API is part of the team that built FriendFeed, which Facebook aquired last year. Taylor says there aren’t any plans to develop FriendFeed any further, but that Facebook will keep it alive.

UPDATED at 2:30pm PDT to include details about OAuth and Facebook Connect.

See Also:

• Facebook Finds its Place in the Location Sharing Landscape
• Facebook Tags Everyone at F8 with RFID Chips
• Up Next For Facebook: Expect More Open Interactions