With somewhere in the region of 1,3bn users, Facebook is the largest ever Internet social engagement phenomenon. With so many people interconnected through the site, information can speedily propagate around the world — without any clear indication whether it is correct — and this has given new life to the phenomenon of the Internet hoax.

Once hoaxes arrived as urgent steps to carry out to remove viruses that didn’t exist from your computer, or warnings about waking up in a bath of ice with no kidneys. On Facebook, one of the most frequently repeated is of the supposed power of making a declaration of rights over the user’s own content to prevent Facebook from using it for financial gain. For the record, declaring that under various (nonexistent) conventions that Facebook has no right to use your data is wholly meaningless.

Here we have the dilemma of using a service provided for free by Facebook, yet we are all keen to protect our privacy. Facebook, a commercial organisation, makes its money from mining our data to offer ever more accurate advertising. Our data is the company’s bread and butter, and it can easily manipulate our feeds to make sure that we see something it deems of interest.

Of course, the company sets valid and, in its view, reasonable terms and conditions — if users don’t like it, they can easily leave. But of course hundreds of millions of people enjoy Facebook, like it (pun intended) for its social aspect, for being able to communicate with friends, family and find like-minded others. Many community organisations, charities and even companies rely heavily on the power of their Facebook presence to reach wider audiences. Yet the hoaxers know that we all react strongly to the word “privacy”.

So, back to privacy. Will you fall for this hoax or any others? Those researching the phenomenon have established that we are likely to fall for one, at some point. The reality is, if a friend who is someone you trust posts something the tendency is to believe it, and be willing to share it with others.

If it seems plausible and relates to something you care about, the chances are you will consider re-posting. This is no different to telling others about something you have discovered. I do not know how many times I have seen articles on the untimely death of Macaulay Culkin (which are not true).

This is not new, and there have been many famous historical hoaxes, especially those involving the then new techniques of radio or photography. Though a misunderstanding rather than a hoax, Orson Welles’ rendition of HG Wells’ War of the Worlds on radio was convincing to many in the 1930s. Think about it: the world’s political climate was tense, the radio news broadcast is a trusted social communication medium, you can forgive the confusion.

The risk with hoaxes on social media is that they can be used as click bait, encouraging victims to follow the link to a website which could compromise or infect their computer or device. Hoaxes purporting to represent apparently authentic campaigns for environmental causes, for or against government policy, or for human rights abroad, can acquire an e-mail and password and use them for malicious intent.

So, while some hoaxes are simply childish entertainment, others do have a cynical side. If you are ever unsure, no matter how well you know whichever friend posted it to Facebook, websites such as Hoax Slayer or Snopes are well-informed and filled with information debunking or explaining the origins of almost every dubious Internet claim.

If you discover someone is sharing a hoax, show them the error of their ways, as the chances are it is spreading through Facebook to thousands of other contacts even as you read it.