The country is divided into 650 areas, called constituencies. Each constituency elects a member of parliament (MP) to sit in the House of Commons, which is the elected lower chamber. The unelected upper chamber is the House of Lords.
In the UK, we use a system called first past the post, where the person with the largest number of votes in each constituency is the winner. In a safe Labour/Conservative, etc seat, where there is a large majority for a particular party, a vote for a different party is therefore essentially a lost vote, unlike with a system of proportional representation, where every vote counts towards the number of MPs a party will have.
Before an election, each party will prepare a manifesto, a document which gives a description of what the party will do if it wins. Politicians will put a lot of effort into their election campaign, often helped by party members or other supporters. Ordinary political activists are often referred to as grass roots supporters or simply the grass roots.
Senior politicians often spend a lot of time travelling around the country on the campaign trail, particularly trying to persuade floating voters, also known as swing voters – people who are not loyal to one particular party, but who change their vote according to issues that matter to them at the time of the election. They will also be active in marginals – constituencies where the current MP has a very small majority.
On the day of the election, people go to the polling stations in order to cast their vote. They put an ‘x’ on the ballot paper next to the person they want to elect, and then put the paper into the ballot box. It is also possible to have a postal vote.
The votes are then collected and taken to be counted. The results are declared by an official known as the returning officer. If the result is very close, the loser may demand a recount, where all the votes must be counted again.
Then, if one party has an overall majority (more than 50% of MPs), it can form a government. If there is a hung parliament (with no party having more than 50%), the biggest party can try to govern on its own, or parties may join together to form a coalition, such as the present one between the Conservatives and the Liberal Democrats.