US President-elect Joe Biden. (Image: AP/Carolyn Kaster)

He has secured more votes than any US presidential candidate in history. He's a conservative compromise candidate for many on the left, and a folksy Castro to those on the right.

But Joe Biden is about to change the US and the world. Here's how:

Paris climate agreement

Biden said he will rally the rest of the world to act more quickly on curbing emissions by reversing Trump's decision to leave the Paris climate accord. This will recommit the US to cutting greenhouse gases by up to 28% by 2025, based on 2005 levels, and could have political repercussions in Australia, further isolating the Morrison government's passive approach.