Marriage Records may only be records of the wedding. However, you may also find the Application for Marriage completed by the bride and groom-to-be. Marriage records may also be corroborated with church records. Check everything for correctness. There could also be a newspaper account of the wedding.
Final papers are the Petition for Citizenship with supporting affidavits filed by an alien in court.
Y chromosome: One of the two sex chromosomes, X and Y. The Y chromosome passes down from father to son. Females do not receive it. As the Y chromosome is passed on through the paternal line, it is valuable for surname based genealogy studies.
Don't assume that all children listed in the census belong to the wife listed. This may be a second wife and the children a combination of "his and hers."
Genealogy is the search for our ancestors. Family history is the study of the lives they led. Using the information from each area provides us with a true picture of our family.