What Facebook really knows about you

Pressing the 'Like' button

Facebook is the fourth most popular website in the UK with over 30 million people using the site each month on computers, tablets or smartphones.

It's hardly surprising that the social network knows a great deal about its users.

If you need proof of this, think about what happens every time you log in.

Social media essentials

When adverts obviously aimed at you appear in the right hand column of your Facebook page, such as "Are you 43 next birthday?"or "Like dining out in Bishop's Stortford?", it becomes obvious that the information in your profile and posts has been searched, mined and used for targeting you.

This is the case even if you thought your profile was 'private'.

The way that Facebook works is constantly evolving, and the continual introduction of new features makes it a challenge for even the most experienced users to keep up.

In the past, Facebook users had the ability to hide their profile from searches beyond their immediate friends using a privacy setting called "Who can look up your timeline by name?". However, this was switched off in 2013, meaning that people other than your Facebook friends can find you.

Graph Search

The more you share about yourself on Facebook and the more friends you have, the greater the chance that the information will be found by people who are not friends. The possibility of this has increased since the advent of Graph Search, a feature which Facebook introduced to the UK in November 2013.

People are using Graph Search to find friends of friends based on interests or locations. So it could be people who like ski-ing, eat in a particular fast food restaurant or work out in a particular gym in a particular town. This can result in them finding you, even if they do not know you.

The search results are based on how much you reveal about your interests and other personal details, your privacy settings, your friends' profile settings and the relationships between you and your friends.

You can't control everything that happens to your personal data on Facebook and other social networking sites, but there are plenty of ways that you can adjust your privacy settings to limit who can see your posts.

Select who you want to see each post

Facebook logo reflected in eye

Facebook recommends that you select the people you want to talk to every time you post by using the 'Activity Log', and also ask friends and other people to remove anything they have shared about you in the past, that you do not want to be found or seen.

However, consider that if somebody has ceased to be a friend, then it is unlikely that they will do this, and your information will remain 'out there'. If the person is still a Facebook friend and refuses to take down the offending item, it may be time to 'un-friend' them.

  • Make sure you choose an 'audience' for each of the individual items of information that you share. Facebook offers you the option to organise your friends into lists, as well as a 'Restricted' list - you can customise your post so that people on this list can't see what you're sharing. This may seem like a chore but you need to think carefully about who might see your posts. Would you want your work colleagues - including your boss - to see the same things as close family?
  • To control which other users can find things you have previously posted, go to the 'Privacy Settings' page and click 'Limit the audience of posts you've shared in the past' which will restrict sight of posts previously shared with friends of friends - or public - to friends only.
  • Of course, people can't 'unsee' what you've posted and may have already shared it with others. Every time you post you should think about the phrase "what goes online, stays online" - it might be much harder to remove something for good than to post it in the first place.

What data does Facebook hold about you?

When you consider every action that you have ever carried out on Facebook - whether it be completing your profile, posting a comment, uploading a photo, 'poking' someone (remember that?) - you may have clocked up hundreds or even thousands of interactions since you set up your account.

Data kept by Facebook

This also includes everything you have ever posted and every friend you have removed since you joined.

  • IP addresses you used (which may also help locate you)
  • Which credit card you have used to make purchases via the site
  • All of the advertisements you have clicked on (back to a certain date).

See all categories of Facebook data users can access about their own account.

But, if you are like most people, you will have forgotten all but your most recent activity.

Facebook and other social networks, however, have a habit of collecting data on everything you do from the moment you sign up - including every time you log in or out.

You can review much of your history simply by logging into your account and looking back over your timeline. For example, all of your messages and chats can be found in your inbox.

Or for a more comprehensive view, you can view your Activity Log by clicking on the padlock icon top right of screen, selecting "Who can see my stuff?", then "Use Activity Log".

Request your data

It is also every user's right to request a complete history log, which Facebook will quickly and readily supply upon request, with password requests made at two stages in the process for security reasons (another good reason not to reveal your passwords to others).

In all, there are 70 different categories of information available on your history, of which Facebook supplies a short explanation of each and where you can find it, by clicking on this link. Do note that the information in some categories is automatically deleted by Facebook after a certain period of time.

All social networking websites will have a privacy policy and it's worth finding it and checking to see how they handle your information. To get you started we've linked to privacy policies for Twitter, Tumblr, YouTube and Pinterest.

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