The most simple explanation of Hillary’s email problem you'll find, we promise

The row over Hillary Clinton's emails has been rumbling on for months and has now suddenly blown up again.

Donald Trump is calling it "criminal" and polls suggest her lead has been severely damaged.

But her team is now saying the FBI might have broken the law by making its investigation public so near to the election.

But what did she actually do - or not do? We've summed up everything you need to know.

What's the big deal about her emails?

The emails date back to 2009 - Hillary's not actually changed that much

This all goes back seven years to when Hillary Clinton started working as secretary of state.

Instead of setting up a state.gov email address she sent both work and personal emails from the address [e-mail].

She had a private server at her home in New York.

During her time in the job, she says she got more than 62,000 emails. She reckons half were official, and the rest were not to do with work.

She claims the personal ones included plans for her daughter's wedding, her mother's funeral and "yoga routines".

"I thought using one device would be simpler, and obviously, it hasn't worked out that way," she once told reporters.

You can say that again.

So what's the scandal?

Basically, she's asking the American public to automatically trust that she's not hidden any awkward information.

Critics point out that using her own server and email address meant that Hillary Clinton had total control over her messages.

As such, she could decide what information should or shouldn't be passed on to government.

She says she's gone "above and beyond" what she was required to do.

But there's also the question of security. Some argue that relying on her own server could have made things easier for hackers and foreign spies.

There's no way to prove if this happened or not.

But we do know that government servers aren't always totally secure. The State Department itself was hacked in 2014.

Was this illegal?

This is all a bit of a grey area, but probably not.

The law at the time said officials using personal email addresses had to make sure any official correspondence was turned over to government.

Hillary Clinton says that did happen, because most of the work emails went to people with government accounts, and so were automatically archived.

In May 2016, the State Department said she went against government policy by not asking permission for her personal email address. But that's not a crime.

Hillary Clinton checking her BlackBerry

Hasn't the FBI already investigated this?

Yes. In July it cleared her from doing anything criminal.

But she didn't come away from it squeaky clean.

FBI Director James Comey said she was "extremely careless" but that no reasonable prosecutor would bring a case against her.

The bureau also pointed out that Hillary Clinton failed to hand over thousands of work emails.

But it decided that they weren't being deliberately hidden because they'd been deleted before the scandal became public.

Her camp has constantly tried to move the focus away from the email row, but Donald Trump seized on it, often calling her "crooked Hillary".

Why is the FBI looking at her emails again?

This was the bombshell the Clinton camp did not need less than two weeks before the election.

FBI director James Comey wrote to Congress saying that the FBI says it's found new emails that might be relevant.

At that stage, he hadn't actually read the emails - he had to wait for a court order.

This is James Comey, FBI director

Now agents are looking to see if these new emails contain any classified material.

It's reported they have 650,000 emails to go through, so it's unlikely that they'll do it before the election.

It's thought these emails were found in a separate investigation into a politician called Anthony Weiner.

Is he really called Weiner? That's unfortunate...

It certainly is, especially when he's known mostly for sexting scandals and photos of what American newspapers like to call his "bulging underwear".

In 2011 the married politician accidentally tweeted a picture of himself in his pants.

At first he said he was hacked, but then admitted sexting several women.

A couple of years later it came out that he was still sexting under the false name Carlos Danger.

But he's relevant to the election because he was married to a woman called Huma Abedin.

She's one of Hillary Clinton's closest aides. She's said to be like a second daughter to the presidential candidate.

Huma Abedin separated from husband Anthony Weiner in August after new sexting allegations

I bet Donald Trump is delighted...?

Like Christmas has come early. This is certainly moving headlines away from those groping claims.

He's calling this "the biggest political scandal" in 40 years.

He says: "The FBI would never have reopened this case at this time unless it were a most egregious criminal offence."

He's enjoying it on Twitter.

What does Hillary Clinton have to say about it all?

Her team wants the FBI to release more information ASAP.

She says she's confident the emails won't change anything from the July investigation.

But she's gone on the offensive too, calling the FBI's investigation "unprecedented" and "deeply troubling".

She's tweeted about it.

Is the timing a bit suspicious?

Hillary Clinton's team certainly think so.

It's come out the US justice department advised FBI director James Comey not to send his letter to Congress so close to the election.

Now the Clinton campaign is warning he might have broken the law.

He's been a member of the Republican Party for most of his life, but isn't at the minute.

Senate Democratic leader Harry Reid wrote his own letter to Mr Comey.

Harry Reid says the FBI may have broken the law

He said: "Your actions in recent months have demonstrated a disturbing double standard for the treatment of sensitive information, with what appears to be a clear intent to aid one political party over another.

"Through your partisan actions, you may have broken the law."

US officials aren't allowed to use their position to influence an election.

How much of a big deal is this?

You can't really answer this one for certain until after the election

But the polls suggest it's having a real impact.

Last week they showed a 12 point lead for Hillary Clinton. That's now been slashed to just one point.

Either way, it means that the final push towards election day will be dominated by a story Hillary Clinton hoped was over months ago.

And even if she still wins, it means the start of a Clinton presidency will be all about emails.

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