Often, the British political system can seem as though it's deliberately making things difficult for those outside it, with its own set of words and confusing rules and regulations. So to help we've put together a guide to some of the key facts and ideas.

Read Politics in plain English A - I

Landslide: An overwhelming margin of victory for a candidate or party in an election.

Local council election: Elections for local government bodies and positions, such as the London Mayor or county councils. Electoral systems vary between areas and types of election.

Manifesto: The document released ahead of an election by each party containing its intentions and promises, should it be elected to government.

Marginal seat: The opposite of a safe seat: a constituency in which support for different parties is very evenly balanced, leading to a close contest in any election held.

Minister: An MP who holds an important office in government - in charge of, for example, education, health, defence, culture or the environment. The most senior ministers comprise the Cabinet.

MEP: A Member of the European Parliament. Each member state of the EU elects a number of MEPs via a system of proportional representation.

MP: A Member of Parliament - an individual elected by UK voters in order to represent them in Parliament.

Opposition: The official Opposition party in the UK is the party that wins the second greatest amount of seats in the House of Commons.

Parliament: A parliament is a country's main law-making institution. It is comprised of a body of representatives - the word comes from the French for 'a discussion', parlement. The UK's Parliament consists of the House of Commons, the House of Lords and the monarch (in what is understood to be a ceremonial role), who meet in the Houses of Parliament to debate and pass laws.

Polling day: The day on which polling stations open for voters to cast their ballots. In the UK, polling days are normally Thursdays.

Polling station: The place where people go to cast their votes. Schools, gyms, churches and offices can all be used as polling stations. At the polling station, voters are handed ballot cards by staff, which they complete in voting booths. Polling stations are open between 7am and 10pm on polling day.

Pre-Budget Report (PBR): The annual progress report which has come before the spring Budget since 1997. It details what has been achieved and sets out the direction of policy before the Budget itself is announced. The PBR is usually delivered every autumn.

Proportional representation: The voting system in place in Spain, Germany, the European Parliament and many other countries. Unlike first-past-the-post where the winner takes all, proportional representation aims to reflect the percentage of votes a party obtains and the percentage of seats it receives. The argument for proportional representation is that it represents an electorate's views more accurately; an argument against is that it leads to weaker governments with the number of competing parties, making passing laws harder.

Proxy vote: An eligible voter can nominate another person to vote on his or her behalf if they have a valid reason, such as blindness or living or travelling abroad.

Prime Minister's Questions: The weekly televised session in the House of Commons when the Prime Minister answers various questions from other MPs for half an hour.

Safe seat: A constituency in which the tradition of support for one party is so overwhelming it's virtually assured they will win any election held. Only occasionally are safe seats 'upset'.

Shadow Cabinet: The Opposition body which reflects the official Cabinet, consisting of individuals who have responsibility for the same subjects as their equivalent government ministers.

Spin: The media practice of presenting facts in a certain way to make them seem better or worse than they are.

Spoiled ballots: An invalid ballot that does not count as a vote. There are several ways in which a ballot can be spoiled - for example, it can be defaced, filled in incorrectly, torn or left blank. A ballot can be spoiled accidentally or deliberately.

Swing: How much support between parties changes over time.

Westminster: Westminster is the area of Central London that is the centre of British Politics. The Houses of Parliament are located in the Palace of Westminster building.

Whitehall: The Westminster Road on which many government departments and ministries can be found; because of this, 'Whitehall' is often used to refer to overall government administration.

Updated: 30/04/2010

Written by Alex Macpherson, picture by Wendy Hobson.