First US Census - 1790
Taken decennially, starting June 1 of the census year
Some states first Census burned so what is "called" the first Census is actually a recreation from earlier State and County individual Census. ex. Virginia
Before 1850, not that helpful
1850 and beyond, better information collected
1860: Names of entire household included, not just numbers
1880: Relationship of members of household to head of house.
(Good to figure out in-laws or others living in the house who aren't spouse and children.)
1890 - most data has been lost in a 1921 fire
Penmanship and spelling were NOT requirements
I can't find my relatives!