It's a bit of a vague question, but I'll have a go. Parliament is basically our Congress, and we have MP's (Members of Parliament) who represent the counties within the UK, they are voted for a minimum of every 5 years or sooner, if the Prime Minister calls an election before then.
For the majority of recent years, we have had 3 main political parties, the Conservative Party, Labour Party and the Liberal Democrats. The two biggest are Conservative and Labour, and they usually get the majority of seats in Parliament, except during the last election, where neither did, and the Conservatives did a deal with the Lib Dems to form a coalition government, which is what we have now.
During the reign of the Coalition, a 'new' (as far as the media is concerned) party has come into the public eye called UKIP, whose main policy is to remove us from Europe, and become tougher on immigration etc. There are lots of articles on this because it threatens the Conservative Party and there are lots of members who expressed racist and discriminatory views before joining UKIP, despite UKIP protesting that despite bring anti-immigration, they are not racist or discriminatory.
David Cameron - Conservative Party Leader and Prime Minister Nick Clegg - Lib Dem Leader and deputy Prime Minister (Due to the Coalition) Ed Miliband - Labour Leader (Currently Leading Polls) Conservative Party - Our Right-Wing Party, still further Left than the Democrat Party Labour Party - The Trade Union's party, further left than conservatives Lib Dem Party - lied to get into power, furthest left and smallest of the big 3 UKIP - Anti-Europe, further right than Conservatives.
A few extra notes for the colonials:
- Rather than electing a President separately, the Prime Minister is selected from the House of Commons and is not subject to election (other than as an MP)
- Technically, the Crown has to appoint a Prime Minister and give assent to all laws. However, actually exercising discretion in such matters would quickly lead to the UK becoming a republic, so the Crown functions as a rubber stamp.
