How is the American president elected?
Contrary to popular belief, American voters do not actually elect their president. When citizens go to polls, they just vote for "electors". These electors then go on to choose between presidential candidates.
There are five main steps to electing a President:
Forty-eight states, plus the District of Columbia, have a winner-takes-all approach to their Electoral College votes. This means that on election day whoever between Joe Biden and Donald Trump wins the popular vote by even a single vote, wins all of the sate's electoral votes.
It therefore does not matter by how many votes the candidates win in each state, as long as they win more than the next person.
In the US Election process, voters merely indicate a preference, but the task of actually electing the president falls to these 538 individual electors to the US Electoral College.
It is possible for candidates to be the most popular candidate among voters and still fail to win enough states to gain majority electoral votes.
In practice, electors almost always vote for the candidate who wins the popular vote.
If an elector votes against their state's presidential pick, they become "faithless". This happened in the 2016 race when seven electoral college votes were cast this way, but the results weren't affected by the faithless electors.
In 2016, Donald Trump had almost three million fewer votes than Hillary Clinton, but won the presidency because the electoral college gave him a majority.
This year, Election Day falls on November 3. Members of the electoral college will then formally meet and vote on December 14, and their votes will be counted, and the winner announced on January 6, 2021.