Census Records in the UK.
A census is a survey of the population. It includes a basic count of the population size but also questions about basic demographics such as age, race, religion, birth, marriage, death income etc
In the UK, an official census is held every 10 years. The next planned census is for March 2021
Personal information gleaned from an official census is kept private for 100 years. However, you can have access to census data from the periods 1801 to 1901
1901 Census in UK
The 1901 Census gives a fascinating glimpse into late Victorian Britain. You can view details here at the National Archives