The process begins with (generally) inter-party elections, popularly known as primaries, in order to zero in on the candidate for each party.
These are state-level elections in which either the general populace or just members of the parties cast their votes in favour of their preferred candidate, who will go on to fight the nation-wide election against the elected candidate from the other party.
Caucuses are local party committees where members come together to choose a delegate who will vote for their preferred candidate. These primaries and caucuses are usually held on different days.
On a special day called Super Tuesday, a number of states vote together, thus making clear names of the potential frontrunners.
Party conventions are held during the period of July to August during election years. Here, delegates officially elect their presidential candidate, who also selects their running mate (the vice-presidential candidate) by then, or a few days later.
The conventions are generally a platform to unify the party and showcase its strength before campaigning commences in full swing.
After the conventions, the candidates focus on travelling the length and breadth of the country, taking their message and policies to the general voters.
More focus is given to swing states, which are states where the decision can go either way, and thus influence the outcome of the election.
Candidates also generally participate in debates usually on ABC, NBC, CBS and Fox News (the four big national television networks). However, this time around only one debate took place between Trump and Harris on ABC.
On the first Tuesday of November of the election year, voters cast their ballots for the Electoral College, and not directly for the presidential candidate.
The case is different in Maine and Nebraska, which use a proportional district-based system.
How popular votes are counted
Popular votes in the US elections are counted at a state level, rather than a national one.
The counting takes place as soon as polling closes on election day. State and local poll officers collect, tally, and verify the popular vote count within their jurisdiction.
Election workers who count the votes in each precinct can come across a combination of in-person votes, mail-in ballots, as well as early votes. They are aggregated at a county and then state level.
The state has procedures to verify this vote count, and once it is done, the governor and designated officials certify the same.
The US President is elected by 538 electors from across the country.
This comprises of the total number of members of the Senate, the House of Representatives, and three electors from the District of Columbia (Washington, DC).
Winner-take-all: The candidate who wins the popular vote wins all the electoral votes in the states (except Nebraska and Maine).
Each state is assigned a select number of electoral votes, which depends on its population.
The presidential candidate who gets 270 out of the 538 votes is declared the winner.
The electors are chosen by the general voters from party nominees in each state.
In December, electors meet in their respective state capitals where they cast the vote for the President and Vice President.
Electoral votes in swing states are more important than those from states that have historically voted for a particular party.
Swing states are the ones where the outcome can go either way.
Moreover, since each state has a minimum of three electoral votes, states with low populations (like Wyoming) are over-represented while those that are densely populated (like California) are under-represented.
After the polling process, on January 6, a joint session of the US Congress (Senate + House) is held at the Capitol -- which the Vice President presides over.
Whoever gets 270 votes is declared the winner. Even if one candidate wins the popular vote, she or he may lose the election if they fail to receive the required number of electoral votes. This has happened only on two occasions—2000 and 2016.
The new President is 'inaugurated' on January 20, when they take the oath of office and officially begin their four-year term.