The House of Commons are the elected members of parliament. They are elected by the citizens so that they represent there views. The House of lords is traditionally regarded as the lower house, but it is the main parliamentary arena for political battle. A Government can only remain in office for as long as it has the support of a majority in the House of Commons. The House of Commons debates new primary legislation as part of the process of making an Act of Parliament, but the Commons has primacy over the non-elected House of Lords. Money related bills concerned with taxation and public expenditure, are always introduced in the Commons and must be passed by the Lords promptly and without amendment. When the two houses disagree on a non-money bill, the parliament Act can be invoked to ensure that the will of the elected chamber prevails. The House of Commons are the people who will know what the people want and as they are given bills to debate they will vote for or against the bill relating to what they think will benefit the people of society. The House also scrutinises the work of the Government - it does that by various means, including questioning ministers in the Chamber and through the Select Committee system.
The House of Lords roles are similar to those of the House of Commons in legislating, debating and questioning the executive. The House of Lords are not elected by the citizens but they are appointed by the queen and they are given a role. Members of the Lords do not represent constituencies, and are not involved in matters of taxation and finance. The role of the Lords is generally recognised to be complementary to that of the Commons and it acts as a revising chamber for many of the more important and controversial bills.
The consent of the Lords is required before Acts of Parliament can be passed, and the Lords can