The Y-DNA is passed down from father to son from generation to generation.  By testing your Y-DNA, you can trace your paternal lineage.  The more you undestand the science behind Y-DNA ancestral testing, the more you will get out of your genetic genealogy experience.  This tutorial provides you with an in-depth look at the science behind Y-DNA testing technology.  Discover the different types of genetic markers found in the Y-DNA and how it allows us to trace our paternal lineage.