For the first time since 1707, the Scots now have their own parliament in Edinburgh, and the Welsh their own national assembly in Cardiff. It is only England, that doesn't have its own parliament. Issues that effect England are decided by the UK government, which consists of MPs from all over the UK.
The principle behind British democracy is that the people elect Members of Parliament (MPs) to the House of Commons in London at a general election, held no more than five years apart. Most MPs belong to a political party, and the party with the largest number of MPs in the House of Commons forms the government.
Houses of Parliament