The first 'real' census was held in 1841, but was rather rudimentary, more of a head-count than gleaning useful statistics. There was no place of birth, no head of household and families were just described as 'in town' or 'out of town'.
There were slight improvements in 1851, but major improvements in 1861 as our image shows. What had been 'FS' in previous censuses, denoting 'Female Servant' was now more fully described as 'domestic servant' or 'scullery maid' etc.