1841 6 June
1851 30 March
1861 7 April
1871 2 April
1881 3 April
1891 5 April
1901 31 March
1911 2 April
All the original returns for these Censuses are available to view on Ancestry, for the United Kingdom countries of England, Scotland and Wales, as well as the Channel Islands and the Isle of Man.
If you are not a subscriber to Ancestry, many Australian libraries have free access on their premises, and some even have a link though their on-line databases that allow access for home viewing.
There are also other on-line transcription databases, such as the coverage found at
https://www.freecen.org.uk/cms/about
which are especially useful as initial indexes prior to viewing the original returns.
For a comprehensive description of the Census process and the records generated, see
http://www.nationalarchives.gov.uk/help-with-your-research/research-guides/census-records/
The 1841 Census has basic information on residence, ages & occupations, and a Y (yes) or N (no) as to whether the person was born in the area being recorded. In many cases, the adults ages are rounded up or down to the nearest 5 years.
The 1851 Census and onwards have increasingly more detailed information, especially as to more accurate ages and place of birth and their relationship to the head of the household.
One thing to bear in mind is that the numbers in the column to the far left of the form are the unique administrative ‘schedule’ numbers that were allocated to each household return – they are not house numbers!
Poor or archaic handwriting can be a very frustrating issue, so see our link to some sites that might help you decipher some puzzling words! Having taken part in several Censuses myself as an enumerator before the days of on-line returns, I can testify that any necessary house-to-house enumeration on cold, wet British early spring enumeration days, when fingers had turned blue and stiff with cold, could be quite a challenge to ensure that the forms were filled in legibly. So spare a thought for those long-suffering enumerators of the 1800s when you are cursing their handwriting!
It was not only houses that were enumerated; from 1851 there are also returns for those on board British ships on Census nights, see
http://www.mariners-l.co.uk/UKCensuses.html for further details of these returns and where to find them.