First Past The Post
‘First Past the Post’ (FPTP) is the colloquial name for the way we elect our MPs in the UK, and local councillors in England and Wales. The country is divided into areas called ‘constituencies’ (constituencies are geographical areas with roughly similar numbers of voters contained within them) and the candidate who gets most votes in each constituency wins, even if their vote falls far short of a majority.
FPTP is now only used in a very few countries, almost all with a British colonial legacy; these include the USA (with an electoral college), Canada and India.
Several countries have rejected FPTP: New Zealand introduced a Mixed Member System in 1996, and South Africa moved to a proportional list system at the end of the Apartheid era.
Advantages of FPTP include the fact that it is simple, and embodies a "consituency link", where people are represented by a local MP who really knows the area. However, the allocation of parliamentary seats under FPTP bears no mathematical relationship to the votes cast in an election, and it sometimes leads to very anomalous outcomes. In 1951, for example, the Conservative Party won an overall majority in Parliament despite getting fewer votes than the Labour Party and in 1974, Labour became the biggest party in Parliament, despite getting fewer votes than the Conservatives. So, FPTP can produce governments that the majority of voters rejected at the ballot box.