The idea underlying both these systems is to secure a representative assembly reflecting with more or less mathematical exactness the various divisions in the electorate. The rest are schemes of minority representation. The difference between proportional representation and minority representation is important.
All schemes of minority representation aim at giving representation of some kind to minorities, but not in proportion to the number of their votes, whereas proportional representation gives representation to minorities in proportion to their voting strength. In both these cases, however, the existence of parties or groups is formally recognised, and each party or group is given special representation.
It must, however, be noted that no scheme of proportional representation can work on the basis of a single-member constituency.
It involves, firstly, a multi-member constituency, and, secondly, the candidate is not elected by securing a relative or absolute majority, but only if he reaches a quota of votes, that is, total number of votes cast divided by the total number of seats determines the quota of votes necessary to get elected.