Meta's $18bn (£13.3bn) settlement with nearly every US state is about more than money.

As part of the deal, Facebook and Instagram have agreed to bring in several significant measures to protect children online - though Meta has not admitted to any wrongdoing.

These include time limits, warnings over screen time and more parental controls over their children's accounts.

At the moment, they will just apply to children in the US - but they could have an impact on the rest of the world.

And if they ultimately set a precedent, other social media companies may be forced to take up the rules, too.

The UK has its own measures in place to protect children online.

The Online Safety Act mainly put restrictions on what content young people can see online.

But the UK government has gone further than the US ban already.

Earlier this year, it announced an outright social media ban for under-16s, which will take effect in 2027.

Some other measures will apply to 16 and 17-year-olds, such as curfews and restrictions during certain hours of the day.

The US has to some extent followed the same path: Start by policing the content on the platforms, then move on to restricting access to social media.

But the core difference is children in the US will not be banned completely.

Instead, they will not have access to Facebook and Instagram overnight, have to follow time limits, and there will be prompts for children who use them for a long time.

Unlike in the UK, these are not put in by law, and will only apply to the two platforms so far (more on that below).

The UK government said it was "following developments closely" in the Meta settlement.

But now those safety features have been accepted by Meta in the US, other countries may start asking for them too.

"These tech platforms don't usually do anything unless they are told to do it," said Trevor Johnson, a former senior figure at Meta and TikTok, who spoke to Radio 4's Today programme.

"But I do think the UK will feel empowered to at least ask for the same restrictions."

Another former Meta director, Zvika Krieger, said Meta agreed to the changes because it saw "the writing on the wall".

"They're trying to demonstrate, 'Oh, you don't need to go and do a complete ban'," he told 5 Live Breakfast.

"I think that they probably would roll out a lot of these features to the rest of the world as well."

Meta may have been the target in this court case, but it has tried to bring the rest of Big Tech into the firing line.

At the same time as announcing the settlement, Meta called on TikTok and YouTube to bring in the same measures.

A Meta spokesperson told Reuters the company was "hopeful" Snap would make similar changes too.

The tech firm has always argued for a level playing field when it comes to regulation - it doesn't want Facebook and Instagram to be more restricted than its rivals, which might be able to hoover up teens who want a freer experience online.

"All platforms should empower parents and support teens in these ways because we know that when teens are restricted on one app, they simply move to another," Meta said.

YouTube, Snapchat and TikTok have maintained they have robust children's safety policies in place.

"There will be pressure for those platforms to adopt similar restrictions," Johnson said.

But they may not come willingly. So far, almost 24 hours after the gauntlet was thrown down by Meta, none have made a public comment.

"Time and time again social media companies don't make changes until they're forced," Ellen Roome, whose son Jools died after taking part in an online challenge, told Today.

Roome is part of a group of parents suing TikTok in the US over child safety.

Meta will pay out up to $18bn to almost all US states, plus the District of Columbia and three US territories.

30% of that is dependent on TikTok and YouTube agreeing to put in child safety measures.

This is far less than the hundreds of billions being speculated ahead of the trial.

It is also a fraction of Meta's revenue of $201bn last year - and Meta will be paying out the money over the course of a decade.

But the firm's future revenue may be affected by a drop in users or younger users spending less time on their platforms.

The complainants will share the money, with different states getting different amounts - but they will get hundreds of millions of dollars each.

New York state, which will receive at least $819m according to its attorney general, said the money would be used "to support mental health services, education programs, and other efforts to repair and reduce the harm caused by unhealthy social media use among young people".

Many other states have said they have earmarked the cash for similar initiatives.

The only two US states not included are Florida, which rejected the settlement, and New Mexico, which was not included in the offer after a previous court cases resulted in a $942m fine.

Former Meta whistleblower Arturo Béjar, who was a witness in the trial, cited the now-familiar comparison of social media with Big Tobacco.

But, he told the BBC, even after companies were found to be pushing harmful products, they "were still able to sell cigarettes and the cigarettes were still as harmful".

Alexa Knight from the Mental Health Foundation gave a different analogy - consumer products.

"We expect the manufacturers to make sure their products are safe before they're released... particularly when there are children using them," she told 5 Live Breakfast.

"And we think it should be the same way for Big Tech."

That is to say, campaigners like Béjar and Knight are not going away.

Roome also said the new measures in place were a start, but don't go far enough.

There will be time limits on app usage, she said, "but what about the content on the platform?"

No one is claiming the settlement is a silver bullet, but it's likely Meta and its fellow social media companies will continue to face scrutiny over the safety of children and adults on its platforms.

One of the issues which triggered this trial concerned how Meta collected and used the data of young people, including those aged under 13.

Social media companies collect vast amounts of data in order to target advertising, and also to work out what kind of content to show each user.

In the settlement agreement, Meta must only use young people's personal data to estimate their age.

If they are under 13, they should be kicked of the platforms, and if they are 13-17, they should be subject to the extra protections for children.

Meta said it would strengthen its age assurance technology to make sure these are robust.

And it reiterated its longstanding call for age verification to be carried out by app stores rather than by Meta itself.

But privacy campaigners have argued in the past that age verification methods require companies to take even more personal data from users.

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