In the USA, the President is elected by the Electoral College. After the United States Presidental Election, 2016, Donald Trump was referred to as President-Elect as soon as his candidacy was projected to have enough electors. Apparently, this is officially recognised, since he met with President Obama and started receiving security briefings. How does it work that Trump is formally recognised as President-Elect when even though he has not yet formally been elected by the Electoral College?
I looked at the Wikipedia entry on the term, where they state this in the opening sentences:
President-elect of the United States is the title used for an incoming president of the United States during the period between the general election on Election Day in November and noon Eastern Standard Time on Inauguration Day, January 20, during which the president-elect is not in office yet.
My assumption was that the term itself was more or less used informally as a general rule and that there weren't any real definitions to when the starting and stopping of using that term to refer to someone. I was wrong, and enter the Presidential Transition Act of 1963 (pdf):
(c) The terms “President-elect” and “Vice-President-elect” as used in this Act shall mean such persons as are the apparent successful candidates for the office of the President and Vice President, respectively, as ascertained by the Administrator following the general elections held to determine the electors of the President and Vice-President in accordance with title 3, United States code, sections 1 and 2.
The term is being used such as to identify who apparently is going to be the next President. Power transitions are tough, especially in times when a big change in direction is most likely going to take place so it makes sense to try to give the incoming President as much time as possible to organize their team and hit the ground running as fast as possible. Absent a precedent-shattering event when the electoral college votes, the apparent winner of the general election will be the next President.
You need to note that the result of the Electoral College vote has already been decided by the popular vote and the decision has never been reversed in the US history before. In other words, the presidential election on Nov. 8th is to choose "electors" who usually pledge to vote for particular candidates. It is nothing but a legal procedure to elect the president.
Of course, it is possible for those electors to cast an electoral vote for someone other than the person pledged or does not vote for any person, but it rarely happened. In addition, 24 states have laws to punish faithless electors.
As electoral slates are typically chosen by the political party or the party's presidential nominee, electors usually have high loyalty to the party and its candidate: a faithless elector runs a greater risk of party censure than criminal charges.
Faithless electors have not changed the outcome of any presidential election to date. For example, in 2000 elector Barbara Lett-Simmons of Washington, D.C. chose not to vote, rather than voting for Al Gore as she had pledged to do. This was done as an act of protest against Washington, D.C.'s lack of congressional voting representation. That elector's abstention did not change who won that year's presidential election, as George W. Bush received a majority (271) of the electoral votes. (Emphasis mine)