Plurality electoral systems are electoral systems where the elected representative is the candidate that receives the most votes, not necessarily the majority of votes
Majoritarian electoral systems are electoral systems where there is a majority required to win- so an individual must receive over half of the votes.
Proportional representation electoral systems are electoral systems in which the votes a party receives are used to allocate seats proportionally
Mixed electoral systems are electoral systems that use a mixture of majoritarian, proportional and plurality systems to determine election outcomes.
First past the post (FPTP) is an example of a plurality electoral system
Supplementary voting (SV) is an example of a majoritarian electoral system.
Single transferable vote (STV) is an example of a proportional representation electoral system
Additional Members System (AMS) is an example of a mixed electoral system