With RCV, each voter ranks the candidates in order of choice: their favorite candidate first, their second-favorite candidate second, and so on.
In single-winner RCV, a candidate needs more than 50% of the votes in order to win. If a candidate receives more than half of first choices, they win in the first round. If not, the candidate with the fewest votes is eliminated, and any voter who picked that candidate as ‘number 1’ will have their vote count for their next choice. This process continues until a candidate wins with more than half of the votes.
The process is similar for multi-winner RCV, but the threshold for winning a seat is lower. For example, if a city is electing 4 people to their city council, each candidate must earn more than 20% of the vote to win a seat.