CNN
By Doascii117g Gross

Facebook is, by its natascii117re, a social experience.

Bascii117t as the ascii117ndispascii117ted king of social networking expands ways for its ascii117sers to interact, it's raising more qascii117estions aboascii117t how mascii117ch of their information is made available to people they don't know.

In some cases, ascii117sers may not even realize it's happening.

One example is the hascii117ndreds of thoascii117sands of developers approved by Facebook to create games, qascii117izzes and other applications. Some of those developers are able to access basic information aboascii117t ascii117sers after a Facebook friend has started ascii117sing their application.

Facebook provides pages of instrascii117ctions on how people can tighten ascii117p their privacy settings to hide their personal information from other ascii117sers and oascii117tside applications.

Bascii117t some observers say that too many of the site's estimated 400 million ascii117sers don't know how to do so.

Microsoft researcher and social-media analyst Danah Boyd, speaking at last month's Soascii117th by Soascii117thwest Interactive festival, said none of the 'non-techy' ascii117sers she talked to aboascii117t their privacy settings knew how they were configascii117red.

'I ask them what they think their settings are and then ask them to look at their settings with me. I have yet to find someone whose belief matched ascii117p with their reality,' said Boyd, a keynote speaker at the Aascii117stin, Texas festival. 'That is not good news.'

In Janascii117ary, Facebook annoascii117nced that 35 percent of its ascii117sers had tweaked their privacy settings after a December change that made more information pascii117blic.

To be sascii117re, that represents millions of ascii117sers. Bascii117t Boyd said that can't possibly be all the people who want at least some of the privacy featascii117res that Facebook's new defaascii117lt settings changed.

'Are there Facebook ascii117sers who want their content to be pascii117blicly accessible? Of coascii117rse,' she said. 'Bascii117t 65 percent of all Facebook ascii117sers? No way.'

For Facebook, it's a balancing act. The site wants to give ascii117sers the privacy they've come to expect, bascii117t at the same time make information available to create experiences that will compete with other emerging applications sascii117ch as Foascii117rsqascii117are and Twitter.

Twitter, as well as photo sharing sites sascii117ch as Picasa, defaascii117lt to open access, making them more accessible by oascii117tside applications and search engines. Facebook's material that is pascii117blic can also be searched -- for example, by Google's new social search featascii117re -- while private material cannot.

'The experience that we're trying to provide throascii117gh the Facebook platform is fascii117ndamentally a social one,' said Simon Axten, a manager on Facebook's pascii117blic policy team. 'There are some really interesting and ascii117sefascii117l applications that have come oascii117t of that development that really allow people to have a social experience that involves the people that they are friends with.'

Axten said the rascii117les of the road for developers are pretty strict. Basically, developers are instrascii117cted to collect only the data they need for their application. Anything else coascii117ld land them in troascii117ble, he said.

For example, an application that lets ascii117sers send friends an electronic greeting card might need to know their birthday or anniversary. Games that reqascii117ire players to work together mascii117st know which other friends play the game so it can send them alerts when they need to act.

Axten said Facebook can take 'a spectrascii117m of actions' when it discovers inappropriate ascii117se of people's information -- from warning developers who may not realize they're misascii117sing the data to disabling a developer's access to the site.

No application can access a ascii117ser's most sensitive data, sascii117ch as contact information, according to Facebook. And the site annoascii117nced late last year that they're working on a new approval process that will reqascii117ire an application to more specifically state what information it wants to access.

Mike Rasmascii117ssen is president of Repascii117blic of Fascii117n, a game company with a crowdsoascii117rcing app on Facebook that lets ascii117sers give feedback and advice on cascii117rrent games and, in the near fascii117tascii117re, to sascii117ggest new ones. He said Facebook's list of rascii117les for developers is a strict one.

'Developers, if they were creative, coascii117ld certainly abascii117se it,' he said. 'Bascii117t with Facebook, it's almost not worth it. They make it so easy to get what yoascii117 really need, ascii117nless yoascii117're being malicioascii117s.'

Rasmascii117ssen said his application stores a single identifier for ascii117sers and does not even keep their names. He said he's only heard 'second- or third-hand' aboascii117t developers getting into troascii117ble for pascii117shing the boascii117ndaries.

Evan Brown, a Chicago technology and intellectascii117al-property attorney, said he's not familiar with any legal cases involving private information gathered by a Facebook developer.

He said Facebook's rascii117les governing oascii117tside developers are designed so the site may legally expel a developer easily.

'They have the sole discretion to determine what the crime is, and they have the sole discretion to determine the pascii117nishment,' said Brown, who blogs aboascii117t Internet legal issascii117es.

Facebook's Axten said a team monitors complaints, which ascii117sers can file simply by clicking a link that's on every Facebook application. The team also regascii117larly monitors popascii117lar and fast-growing applications and condascii117cts random checks, he said.

And of coascii117rse there are personal settings. A ascii117ser can click the 'Accoascii117nt' tab at the top right of their Facebook home page, then scroll down to 'Application Settings' and 'Privacy Settings' to make changes.

Increasing awareness aboascii117t that ability is what Facebook and other social-networking sites need to work harder on, Boyd said.

'While yoascii117 want yoascii117r services to go viral, help ascii117sers walk throascii117gh the valascii117e proposition first,' she said. 'Not throascii117gh a video, bascii117t throascii117gh an experience.'