Hare system

Also known as the single transferable vote formula. The Hare system was developed in the nineteenth century by Thomas Hare, a British political reformer, to create constituencies with multiple representatives in electoral systems based on seeking proportional representation. Ballots are used on which a voter may rank his or her choices in order of preference. Any candidate who has received enough first-preference votes to meet a quota wins a seat. Votes above this quota are transferred to the candidates with second- preference votes, and each of those who meet the quota is awarded a seat. The process continues until all seats in a constituency are filled.

Source: Library of Congress