The presidential election determines the country’s leadership and shapes issues at local, state, and national levels. From whether your child’s school gets resources to what happens at the border with Mexico, your life is deeply impacted by the people elected to govern our country. This is why it’s important to get out and vote in every election.

The Electoral College system prevents candidates from focusing solely on high-population urban centers and dense media markets, forcing them to seek support from a wider cross-section of Americans. In addition, it ensures that any candidate winning a majority of the popular vote will become president.

However, the system has its critics. It can lead to electoral ties and prolonged recounts (like what happened in Florida during the 2000 election), and it has been criticized as undemocratic and anti-competitive.

Data journalist and FiveThirtyEight co-founder Nate Silver pioneered this type of forecasting when he began putting together polling data, building models, and constructing probabilities for each election in 2008. The practice has gained popularity, and many news outlets now regularly feature these predictions on their websites and in their coverage.

In December, “electors” from each state — except Maine and Nebraska — gather to tally their votes for president. The candidate with the most electoral votes wins. Unless there is a deadlock between the top two contenders, when Congress meets in a joint session on January 6, one of the top three vote-getters becomes president, and the other two act as vice presidents.