You might have seen it on your timeline, the ultimate shut down: "You are fake news!"

US President-elect Donald Trump used it on Tuesday and since then for some people it's become a go-to response for anything they don't like.

But Jon Bernstein, a journalist and digital media consultant, thinks this current craze is more significant than it seems.

He's been chatting to Newsbeat about why Mr Trump's choice of words matter.

What's this all about?

It's all to do with what looks like a US intelligence dossier which has been published by Buzzfeed.

They don't know whether it's real, but, if it is, they think it was written by a former British spy.

It contains claims that Russia has embarrassing footage of Donald Trump which they could use to blackmail him.

But in a dramatic press conference Donald Trump dismissed it as "fake news".

The shut-down inspired the internet.

Deliberate fake news became a big talking point in November

Donald Trump's use of the term is nothing new, fake news was in the headlines a lot before and after the US Election.

Political news stories without a shred of truth in them, claims that the Pope was backing a particular candidate, for example, were found to be circulating on Facebook.

Fake news is news that is untrue perhaps deliberately put into the public domain in the knowledge that it's untrue Jon Bernstein Digital media consultant

"I think fake news is sinister to some extent," explains Jon Bernstein, "there are people out there who are basically news farms producing fake news because it is a way either of influencing the news agenda, the political agenda, or quite simply [a way] of making money.

"The more people read your fake news the more advertising you can sell, the more money you make."

Unverified news is very different

Despite President-elect Trump's cry of fake news, what happened in the case of the supposed US intelligence dossier is a very different thing.

And that's because Buzzfeed has published information that it doesn't know is true or false.

"There is an important difference between fake news and unverified news," Jon Bernstein explains.

Unverified news is news that hasn't yet been proved to be true or false Jon Bernstein Digital media consultant

"Fake news is news that is untrue and perhaps deliberately put into the public domain in the knowledge that it's untrue, whereas unverified news is news that hasn't yet been proved to be true or false."

This doesn't mean, though, that unverified news can't be harmful. Several news organisations had a copy of the dossier but decided it wouldn't be responsible to publish it.

Why does it matter?

By confusing the two, Donald Trump might have been doing something quite clever.

"Maybe he deliberately mixed those two things together.

"It certainly suits him to do that because if he dismisses the story as fake news, and fake news has got this currency that it's a sinister thing, then he's saying you can dismiss it out of hand.

"The truth is it may be false, but at the moment it's unverified and that's a very different thing."

And it's possible Mr Trump was taking advantage of the current fashion for calling allegations "fake news".

"There's a real irony here, Donald Trump's jumping on the fake news bandwagon for sure and a lot of the fake news that was out there was very beneficial to him during the election campaign.

"Now he's using the term fake news to dismiss out of hand the work of some news organisations.

"To mix the two things together suits Donald Trump very nicely indeed."

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