There are often misconceptions about how government works in the United Kingdom, so it's worth setting matters straight here.

Ultimately Parliament derives from the Witangemot, the meeting of 'wise and great men of the kingdom' that would elect the new king of Wessex from members of its royal family, and then advise him. The Witan was based in the West Saxon capital of Winchester, hence the name (originally Wintanceastre). When Wessex became the dominant part of a united England, this tradition continued.

The Norman Conquest, however, instituted a new Continental notion of an absolute monarchy inherited by direct primogeniture. The Witan died with the Anglo-Saxon nobility. The idea, however, did not. In the 13th century, Norman monarchs starting with Henry III began calling new Parliaments (from French parlement, a place for talking) consisting of their nobles and senior churchmen. A significant milestone was when Simon de Montfort called the first elected parliament in the 1260s (with a franchise that was actually wider than it would be again for many years to come) during his rebellion against the King. Montfort is now honoured as one of the fathers of democracy by both Britain and the United States.

As Parliament grew in power, the fifteenth century saw the franchise being restricted to those who owned property equivalent to forty shillings. This number remained unchanged with inflation in England (though not in Scotland) however, so the percentage of the population that could vote slowly increased over time.

The seventeenth century saw King Charles I, who had absolutist ideas, trying to rule without Parliament - even though he needed Parliament's authority to raise taxes to fund his wars. This resulted in the English Civil War, which was itself only a part of the Wars of the Three Kingdoms in England, Scotland and Ireland. Parliament fought the King and won, with Charles being executed and Parliamentary leader Oliver Cromwell ruling the new republican regime as Lord Protector. However, he too soon dissolved Parliament, finding it unworkable and leading to the Parliamentarians looking hypocritical.

After Cromwell's death, Charles' heir came back as Charles II and the Stuarts ruled for about thirty years. However, when the Catholic James II came to the throne and was rumoured to have produced an heir, the Glorious Revolution occurred. William of Orange, the Dutch Stadtholder married to James' daughter Mary, came over with an army and kicked the Stuarts out of the country. The Parliament of England recognised William and Mary as joint monarchs, hence why this is known as the Glorious Revolution and not the Dutch Invasion With Excellent PR. This marked the time when the monarch's role became decidedly secondary to Parliament.

Between the Glorious Revolution (1680s) and the Great Reform Act (1830s) Britain was governed by ministers theoretically chosen by the King from Parliament, but in practice this only worked if those ministers already enjoyed support among their fellows. Party lines meant little in this era - MPs were usually elected on the basis of their individual personality or the family they came from, and then chose to join a faction after they had been elected. Each county elected two MPs (the origin of U.S. states electing two senators each) and then large towns and cities, 'boroughs', also elected either one or two MPs. However, new boroughs had not been introduced for a long time, leaving large new cities like Manchester without representation. Also, old boroughs for places that had been thriving cities in the Middle Ages but had now been largely abandoned were not cancelled, so hamlets of five people continued to elect two MPs. These were known as the Rotten Boroughs, and for much of the 18th and 19th centuries, parliamentary reform was aimed at abolishing them.

The power of the King was reduced over this period, partly because the new Hanoverian monarchs often did not speak English and were more interested in their European possessions. The 1720s saw the South Sea Bubble, a financial scandal which meant most of the King's ministers resigned. Their powers were amalgamated by the one senior minister who had escaped charges, Robert Walpole, and he became the first Prime Minister - a title which, until the 20th century, was a pejorative one. After the loss of the American War and the madness of King George, William Pitt the Younger became PM. Beginning as a liberal reformer, both he and Parliament in general became more and more conservative in reaction to Revolutionary France, the enemy in that period. This ended with the 1810s and 1820s, in which British popular reformers, the Chartists, had their demonstrations crushed by British troops in controversial actions such as the Peterloo Massacre.

This ended in the 1830s when the PM, Earl Grey (famous for tea) passed the Great Reform Act. This got rid of the rotten boroughs and changed the electoral system so that each constituency now only elected one MP. However, the fact that Oxford and Cambridge Universities both elected MPs from their own faculty was retained until after the Second World War. Universal male suffrage did not happen until after the First World War.

A general election is called. Various parties nominate candidates for a constituency and they stand. Whoever gets the most votes (“first past the post”) is elected MP. The House of Commons is made up of 600-odd elected MPs. Whichever party has the most MPs forms the Government, while the second largest becomes the Official Opposition. Usually a government must have a majority in order to govern effectively - coalition governments are rare in Britain. The Queen then (theoretically) picks the Prime Minister from among the largest party, but in practice Her Majesty always chooses whoever that party has already chosen to be their leader. The new Prime Minister chooses his Cabinet ministers from among his party's MPs and Lords, while the Leader of the Opposition picks Shadow Cabinet ministers, whose role is to criticise their counterparts.

One of the most entertaining parts of British politics is Prime Minister's Question Time, in which the Leader of the Official Opposition gets six questions to ask the PM, and the leader of the smaller opposition party gets two. These questions are usually something along the lines of “In light of recent events, does the Prime Minister agree that his government is hopelessly incompetent?” and then the PM has to cleverly twist this into an attack on the Leader of the Opposition's party's record when they were in power. When in Parliament, MPs are always referred to as “the honourable gentleman” or “my honourable friend”, unless they are on the Privy Council, in which case they are “my right honourable friend” or “the right honourable gentleman”. Lords are referred to as “the noble lord”.

The Privy Council is essentially the Cabinet ministers plus a few semi-ceremonial offices and the Leader of the Opposition. This was formerly the highest court of appeal in the British Empire: for example, when Canadian suffragettes had failed to get their government to agree to let them stand for public office, they appealed to the Privy Council of the United Kingdom, which overruled the Privy Council of the Dominion of Canada and let them stand.

The House of Lords has lost many of its powers over the years but is essentially an unelected body intended to peruse and criticise Commons legislation from a less partisan viewpoint. The Labour Party recently abolished many of the former hereditary peers and replaced them with appointed 'life peers' who, purely coincidentally I assure you, were mostly old mates of Tony Blair. The Lords generally cannot shoot down Commons legislation these days but it can keep endlessly sending it back for revision. The exception is the Parliament Act, which the government can use once every session to force a piece of legislation through: Labour has recently been using this much more often than was formerly the convention. Although the monarch's powers are these days mostly theoretical, bills do not become law until they receive Royal Assent. It is also the Queen's role to dissolve parliament and call a general election, although in practice this almost always happens because the PM has asked Her Majesty to do so.

New Labour tried to move the UK towards federalism by introducing devolved parliaments in 1999. These consist of the Scottish Parliament, the Welsh Assembly and the Northern Ireland Assembly, as well as the London Assembly. All of these are elected on a hybrid proportional representation basis. Nationalist and minor parties typically do much better there than at Westminster. There have been some moves towards an English parliament as well; Labour originally wanted parliaments for each English arbitrary region, but this was soundly defeated in a referendum.

Every two years, one-third of local councils (in England and Wales; Scotland has a different system) are up for election. These days, the media slavishly follows these elections and uses them to try and say something about Westminster, even though most people elect local councillors based on local issues rather than party.

Labour Party: Currently in power led by PM Gordon Brown, but for how long? Started out around the turn of the 20th century as the radical socialist party of the working man. After actually gaining power in the 1920s it drifted toward the centre-left. The 1945 postwar Labour government embarked on a programme of nationalisation, of which the National Health Service is the most important product. This 'socialist consensus' was allowed to stand by other governments until 1979, when Labour lost power to the new strongly rightist Conservatives. Labour turned to the hard left and became virtually unelectable for years - shedding its right wing as the Social Democratic Party - until first Neil Kinnock and John Smith, and then especially Tony Blair, brought it back towards the centre. Blair in fact got rid of almost all the economically socialist parts of the party, but kept the social aspects. Even though many Labour backbenchers were 'Old Labour' socialists, this system held together for years - but now appears to be breaking down. Their colour is red and their symbol is the rose.

Conservative Party: Currently in opposition. Began in the 1830s, but ultimately descends from the 17th-century Tory Party (its members are often still called Tories). Traditionally right-wing on both economic and social issues - the latter being known as either the “Flag, Faith and Family Group” or the “Taliban Tendency”, depending on who you talk to. This is basically the British version of the Religious Right. In 1951 the Conservatives decided to accept the Labour-penned 'socialist consensus' and this persisted until Margaret Thatcher became Britain's first female PM in 1979. The Thatcher government privatised absolutely everything and enacted many economic reforms which either made everything much better or far worse, depending on who you ask. Thatcher continues to polarise opinion more strongly than any other politician in British history. After losing to Blair in 1997 and spending many years in the political wilderness, the Conservatives now seem tipped to be the next government under their leader David Cameron. Also the party of colourful former MP and current Mayor of London, Boris Johnson. Their colour is blue and their symbol is the tree, formerly the flaming torch.

Liberal Democrats: Originate from the old Liberal Party, formerly a major 19th-century party but a victim of its own success when the voting system changed. The last nail in the coffin was when leader Jeremy Thorpe turned out to be in a gaysexual relationship with a male model in the pocket of a Soviet spy ring. The last remnant of the Liberals then joined with the SDP, a breakaway Labour faction (see above) in the 1980s to form the Liberal-SDP Alliance. This eventually became the Liberal Democrats, or Lib Dems. They are Britain's third-largest party and their ambitions for power are chiefly limited to being the decider for forming a coalition government in a hung parliament (where there is no overall majority). The Lib Dems' support base is chiefly students and people in very isolated parts of the UK, e.g. Cornwall. The one policy of theirs everyone can name is their commitment to change the electoral system to bring in proportional representation - which would, purely by coincidence I assure you, result in them winning many more seats. Their colour is yellow or orange and their symbol is a stylised bird.

Plaid Cymru: Welsh nationalist party, in theory wanting independence for Wales, but in practice probably not willing to go that far. Pronounced 'plyde cummry'.

Scottish National Party: Wants independence for Scotland and probably actually means it. Has done very well recently. Notably supported by Sean Connery.

Ulster Unionist Party, Democratic Unionist Party and UK Unionist Party: Various Northern Ireland loyalist parties committed to the union with the UK, with varying degrees of frothing-at-the-mouth-ness. The most extreme of them, the DUP, is currently the most powerful.

Sinn Fein: Originally with ties to the IRA, has recently become more moderate. Wants Northern Ireland to join with the Republic of Ireland (and also runs candidates in the Republic). Pronounced 'Shinn Fayn'.

Alliance Party: Attempt at forming a religiously non-partisan group in Northern Ireland, not with much success.

Social Democratic and Labour Party: A Northern Ireland party which leans towards joining the Republic but is not rabid about it, and is thought to be considering merging with the Republic party Fianna Fail.

Green Party: Far less successful than the ones in Europe, but has managed to get several councillors and London Assembly members elected. Are targeting Norwich at the next election as their best chance for getting an MP. Obviously environmentalist and generally socially liberal. They only very recently decided to choose a single leader, previously having several spokesmen.

British National Party: The newest and most scrubbed-up variation of Britain's far-right fringe. The BNP is universally loathed and despised in the media and certain sectors of society, but this often simply has the effect of making it a forbidden fruit. Originally a cut-and-paste Nazi group, it was considerably reformed by current leader Nick Griffin to suit modern attitudes - for example, rather than being anti-Semitic, it now supports Israel as an 'outpost of civilisation' against the Muslims, who are its main targets.

UK Independence Party: A single-issue party, otherwise Conservative in attitudes, that wants Britain to withdraw from the European Union. Their colour is purple.

Minor far-left parties: For example the Socialist Workers' Party, the Socialist Labour Party, and so forth. The only one to have any electoral success is “Respect - the Unity Coalition”, which is really run by the SWP behind the scenes.

Mebyon Kernow: The Cornish nationalist party, but no-one can stop laughing long enough to take it seriously.

English Democrats Party: Advocate an English devolved parliament.