He's the reality TV star known for having lots of money and even more confidence. But now he's set for his biggest challenge: becoming the President of the United States.

Something very few people saw coming.

But, now it's happened, many of you have told us you're feeling a bit concerned about what might happen next.

STUDENT: I did go home with mum and dad and I started watching it as well after he actually won and yeah, I thought it was crazy.

STUDENT: Every time Hillary was in front it was like 'yeah, Hillary. Oh, wait, no, it's Trump again, oh no!'

But what might a Trump presidency actually look like for the U.S and the rest of the world? To work that out, it helps to know more about the man who will be named president in just a few months' time.

Trump was born in 1946 into a very rich family. He studied economics in college and once finished, his dad gave him a huge amount of money to help kick-start his career in property development. Since then, he's built casinos, offices, hotels and golf courses around the world.

Trump has always enjoyed the spotlight, and throughout the campaign he regularly made headlines, by saying controversial and sometimes very negative things about women and people of other races and religions.

Some of the promises he made during the campaign made a lot of people angry as well, like his idea to build a wall between the US and Mexico to keep out illegal immigrants or banning Muslim people from entering the United States.

So, how did he end up winning? Well, lots of Americans say they don't think their politicians are very effective or trustworthy. So, they wanted change. Trump supporters saw Donald as a way of making that happen, because he's never been in politics before. And because he's already really rich he didn't have to rely on donations from big companies to get there, so, they think he'll be more independent.

Another big factor in Trump's election, is that lots of people in rural America say they're feeling forgotten. So, throughout the campaign, Trump promised to help these areas and stop a lot of their jobs moving overseas.

Around the world, many people are wondering how Donald Trump's leadership might affect them too. Some say it's likely he'll make international trade more expensive. Others say he'll reduce the amount of money the US spends fighting climate change.

But while some things might change over time, experts say there's nothing for kids to worry about right now. Many world leaders say Trump deserves to be given a chance.

BARACK OBAMA, US PRESIDENT: We are now all rooting for his success in uniting and leading the country.

And Trump himself says he's going to work hard to bring all Americans together.

DONALD TRUMP, US PRESIDENT-ELECT: I pledge to every citizen of our land that I will be President for all Americans.

So, what would your advice be for the new President-elect?

STUDENT: My advice to Donald Trump would be to think before he speaks and makes promises.

STUDENT: I think that he should show a bit more respect to Muslims, people of other races and genders.

STUDENT: Keep free trade because otherwise you're not going to get much stuff in America and it's going to be harder to export stuff.

STUDENT: To stay strong and be a positive role model.

STUDENT: To keep making jobs for Americans.

STUDENT: Just to be a better person.