Facebook’s secret rules and guidelines for deciding what its 2 billion users can post on its site have been revealed for the first time in a Guardian investigation.

The expose is expected to fuel the global debate about the role and ethics of the social media giant.

Some critics in the US and Europe have demanded that the company be regulated in the same way as mainstream broadcasters and publishers.

The Guardian says it’s seen more than 100 internal training manuals, spreadsheets and flowcharts giving unprecedented insight into the blueprints Facebook use to determine if posts are too violent, sexual, racist, hateful or supported terrorism.

The internal manual shows how the social media site tries to strike a balance between allowing cries for help and discouraging copycat behaviour.

There are even guidelines on match-fixing and cannibalism.

The Facebook Files illustrate difficulties faced by executives scrambling to react to new challenges such as ‘revenge porn’.

It also highlights the challenges for moderators, who say they’re overwhelmed by the volume of work, which means they often have ‘just 10 seconds’ to make a decision.

One source told the Guardian that ‘Facebook cannot keep control of its content,’ adding that “it has grown too big, too quickly”.

Many moderators are said to have concerns about the inconsistency and peculiar nature of some of the policies.

Those on sexual content, for example, are said to be the most complex and confusing.

The expose into the difficulties faced by Facebook in controlling content on its site comes almost two weeks after Information Minister, Ruel Reid, told the Senate there may be a need to regulate social media.

Days later, the Minister walked back the suggestion saying the government is opting for ‘self-regulation’ instead.

It’s understood that the Office of the Prime Minister had shut down Senator Reid’s suggestions.