The Peerage of the United Kingdom is a system of titles of nobility that includes ranks such as duke, marquess, earl, viscount, and baron. These titles are often hereditary, passed down through generations, but can also be granted by the monarch. The peerage plays a significant role in British history and society, influencing politics and culture. Members of the peerage may sit in the House of Lords, one of the two houses of the Parliament of the United Kingdom. While the House of Lords has undergone reforms, some hereditary peers still retain their seats, alongside life peers who are appointed for their lifetime.