A "Groups" feature that lets Facebook members set up private online havens for clusters of family, co-workers, teammates, or others was unveiled at a press event at the firm's headquarters in the California city of Palo Alto.
Founder Mark Zuckerberg said that the "biggest problem" in online social networking is that people tend to divide their friends into separate circles that they interact with differently, such as co-workers or former school chums.
"Now, people can map out all the real world groups they have in a graph," Zuckerberg said, referring to "Groups."
"If we can do this, we can unlock a huge amount of sharing people want to do that they don't do now because it's too annoying or the privacy," he said.
Groups is a shared space in which people can communicate with tools including email lists and "group chat that is pretty killer," he added.
"We think that what we have out of the box, version one, blows away everything else," Zuckerberg said, referring to "groups" services offered by Internet stalwarts such as Yahoo! and Google.
Facebook also began rolling out a feature that will let people download all pictures, video, comments and other digital information they have uploaded to the social networking service.
"Download is really so you can have a copy of all your information," Zuckerberg said. "You own your information. You should have control over it. You should be able to do whatever you want with it."
A new "dashboard" feature to be rolled out in the coming days will let Facebook users see and manage what information in their accounts is accessed by third-party applications.
Explaining the new features, Forrester social computing analyst Augie Ray said "the dialogue during the past year that popped up over privacy issues may have caused people in Facebook to get nervous.
"What we are seeing today is a genuine desire to stop those concerns while at the same time really give people better control," Ray said.
The new features are part of a drive to build Facebook into a "social platform" where people share and connect across the gamut of applications used to swap pictures, messages, videos and more online, according to Zuckerberg.
We think social can be like the PC (personal computer) platform, giving people control of their information in different contexts," he said.
"Groups" was built with the help of Hot Potato, a young New York City Internet firm that Facebook bought in August.
Hot Potato about nine months ago launched a social networking service that lets smartphone users "check-in" to let friends know what they are thinking, watching, playing, attending, listening to, or otherwise doing.
The acquisition appeared to be another step in a vision by Facebook to become a collective memory of sorts, letting members tie their experiences and thoughts to locations for posterity.
"Groups are about how we are living our lives today," said Hot Potato founder and Facebook Groups leader Justin Shaffer. "We think this is going to change, fundamentally, how you use Facebook today."
People forming Facebook Groups can make them either open, closed, or secret.
embership and content of open groups is public, while the content of closed groups can only be seen by members. Secret groups hide their membership and contents.