Social-networking site Facebook is set to increase its sphere of influence by making people listed in its directory visible in search engines such as Google and Yahoo.

See also: Facebook: the most dangerous site on the web?

Existing users logging in to Facebook learnt of the plans only this week where they were greeted by a pane on their profile home page informing them of the plan to make Facebook profiles public.

Privacy warning

Privacy warning

Privacy concerns have already been raised about the successful social-networking site since it transpired that Facebook users were routinely posting details such as their date of birth, mobile phone number on the site.

Unless users are careful to restrict their profile visibility to their trusted group of friends, posting such details means Facebook users are leaving themselves ripe for exploitation by identity thieves.

Along with information such as where you live, your occupation and other details that make you personally in identifiable, a data thief could very easily pose as you for the purposes of credit card applications and other exploits.

Such risks with Facebook have been highlighted in the media (by PC Advisor, among others) but many users continue to display detailed contact and personal information. This advice is even more important now that Facebook is going public.

According to the message from Facebook, the public search listing will begin in a few weeks' time, giving users a couple of weeks to edit any content and alter any settings they don't want the world to be able to find.

A statement on the About pages of Facebook this week reads: "Starting today, we are making limited public search listings available to people who are not logged in to Facebook… The public search listing contains less information than someone could find right away after signing up anyway, so we're not exposing any new information and you have complete control over your public search listing."

While there are indeed tools to limit the amount of information others can see about you on the Facebook site, the default settings allow anyone to view information about anyone in their extended network – in other words, details of friends of friends of friends.

Even so, anyone logging in to their Facebook profile today will see preferences for newsfeeds and other events, where they can choose to display more of less information about themselves.

Find out how to secure your Facebook profile on page 2 >>

Edit your Facebook profile to secure your data

dob privacy

To edit your profile and privacy settings, log in to your Facebook account, then use the Edit option next to each entry to remove some or all of your date of birth entry. Further down the page you can clear entries relating to your email address, employer's address and phone number as well your mobile phone number.

Privacy overview

Privacy overview

Alternatively, Facebook has now made it easier to control who can and can't view information about you. Click the Privacy option at the top of the screen and then alter the Profile and Search settings to restrict who can and can't find you. Lower down this page are options governing what others are able to do having found you online via your Facebook profile.

even and content tags

Another important change is to the Photos and Videos pages. Click on Profile (from within privacy) and alter the photo tagging and video tagging dropdown menu options from All my friends and networks to either Only my friends or even Only me. Oddly, there is no option under Contact Information, further down this page, to completely hide your IM (instant messaging) screen name, mobile or landline phone number, address or website. You can, however, keep your email address to yourself here.

Newsfeed preferences

Click on the Preferences option by the News Feed list and you can then select whether Everyone can see the applications you've installed and recently used.

Newsfeed preferences

Facebook has rapidly become an online means of expression for the social networking site's millions of fans, with videos and photos being posted, users sharing likes and dislikes about music, books, films and pet peeves, as well as voting in polls. This also makes it both a voyeur's and a marketing man's dream, allowing all but untrammelled access to the tastes and whims of whole swathes of the populace.

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