Like the United States, the British have taken regular censuses. The first censuses were taken far back in history and were primarily designed so that the king or queen would know how many soldiers they could marshal during wartime and to assess the total property which could be taxed. In England, the first census that contains genealogical data is the 1841 census.
Since 1841 a household census has been conducted in Britain every ten years except 1941 (due to World War II). The census includes all individuals who were staying in the household on the night of the census. The dates of the census are: 1841 – June 6, 1881 – April 3, 1851 – March 30, 1891 – April 5, 1861 – April 7, 1901 – March 31, 1871 – April 2, 1911 – April 2 (wiki.FamilySearch.org). The census information has changed a little over the years, but these censuses, like in the United States, are some of the most useful records for discovering ancestors and their relationships as families.
A full index of the names in the census can be found for free at FamilySearch.org. Images as well as an index to the names can be found for a fee at FindMyPast.com and Ancestry.com since The National Archives of the United Kingdom derives a royalty from every image viewed.
For privacy reasons the details of the individual records in the UK Census are not released for one hundred years. It was only last year that the details of the 1911 census were made available.
FindMyPast currently has a special rate to view the census images and view a full transcript of the record (they provide a limited transcript for free). The cost is currently only approximately $1.70 to view an image and about $.85 to view the full transcript. The subscription rate is approximately $172 per year for the access to their full collection. These special rates are only available until January 31.
If you have British Ancestors, FindMyPast has one of the most extensive collections and the current pay per view rate is one third of their normal rate. This makes they next few days a great time to have a look at the 1911 census. FindMyPast remains one of my favorite sites for British research. They have good quality indexes and an excellent search system to find their records. I also like the flexibility to pay as I go for full indexes and images or to buy a subscription if I am going to be doing many searches. Like many subscription sites, FindMyPast can also be accessed for free at the Family History Library in Salt Lake.