First past the post is a method of voting, wherein voters mark one candidate as their favoriite, and the candidate with more first-preference votes than any other candidate (a plurality) is elected, even if they do not have more than half of votes (a majority).

This forces the voter to strategize and vote for what they think is the ‘least worst’ candidate that has a chance to receive the most choices, rather than their favorite candidate. It’s therefore probably one of the worst form of election, as it encourages status quo, gerrymandering, and voting based on popularity rather than ideas and programs.

For a more democratic electoral system, see for example single transferable vote.