NEW YORK — Facebook is spreading its wings to the broader Web with new tools that will allow users to see personalized versions of websites they visit elsewhere.
The move could change the way people experience the online world, though it could come with deeper privacy implications. By accessing Facebook's tools, websites will be able to customize the experience based on the list of friends, favorite bands and other things users have shared on their Facebook profiles.
"The Web is at a really important turning point now," Facebook CEO Mark Zuckerberg said at a conference for Web and software developers in San Francisco. "Most things aren't social and they don't use your real identity. This is really starting to change."
It already has, with Facebook among its earliest pioneers. The world's largest online social network has long insisted, with varying success, that its users go by their real identities when they sign up for the service, offering a contrast to the culture of pseudonyms common elsewhere online.
And Facebook has sometimes transported those identities beyond its own service.
The latest changes take this a step further. It means Facebook users will be able to see a Web tailored to them based on their interests and social connections, as long as they are already logged in to Facebook. So when visiting a news site for the first time, they could see which of their Facebook friends liked recent articles. A music site such as Pandora, meanwhile, could start playing music from the user's favorite bands.
Users will also be able to share items on their Facebook profiles without leaving the other websites, simply by clicking "like" buttons next to the news article or other items they are reading.
Zuckerberg told developers at the f8 conference that the experience will mean a more personalized, social, smarter Web.
"There is an old saying that says when you go to heaven, all of your friends are there and everything is just the way you want it to be," Zuckerberg said during his keynote, wearing sneakers and a dark sweat shirt. "So together let's make a world that's that good."
Precisely because people use their real identities on Facebook, and share things they don't want the world to know, the company's latest plans could backfire if it doesn't make it clear what it's trying to do.
"How many people are really going to want all this information about them shared?" said Greg Sterling, an Internet analyst who also writes for SearchEngineLand.com. "That's the big unanswered question here."
Facebook has had some high-profile privacy fumblers. In 2007, its Beacon tool caught users off-guard as their activities at other Web sites got broadcast on Facebook – alerting friends, for instance, of holiday gifts just bought for them. Facebook later gave users the option to turn it off before the company killed the program completely.
This time, though, Zuckerberg said Facebook made sure that its new tools don't intrude on their privacy. Users' preferences won't be logged unless they choose to press the "like" button on websites. If anything, Zuckerberg expects the "like" tools to give people more control over what they want to share with their online entourages.
If users embrace it, Facebook could gain valuable insights that could help it sell more advertising, potentially rivaling online ad leader Google Inc., which typically tailors ads based on keywords in search terms and Web content.
"If I were Google I would be really scared because Facebook might end up with a lot more intelligence than them," said Alain Chuard, founder of social marketing firm Wildfire. "Google is just an algorithm, but Facebook could rule the Web."
Ads on social networks still make up a small percentage of companies' total online advertising budgets. But the space is growing, with Facebook at the helm. In the U.S., research firm eMarketer expects companies to spend $23.6 billion on online ads this year, with 5.5 percent of it going to social networks, up from 5 percent in 2008.
Zuckerberg, who turns 26 next month, initially expects the new tools to generate more revenue for other websites and outside developers than his own company. But he also acknowledged that as Facebook gets a better grasp on its users' interests, "a lot of other things become possible."
Liedtke reported from San Francisco.