Paternal or Y-DNA. The traditional view of Family Trees where only male's descendants are included. Y_DNA is Y Chromosone. One of twenty-three Chromosones it defines Gender; Around 4% of a Person's DNA. It is passed from Male to Male only through Sperm. Patrinomics, Surnames, Family Names, became the norm in the Medieval Period. Earlier surnames are invented.
Maternal or mtDNA. Maternal Family Trees include People who share the same mt-DNA; passed through the Female line only.