Seth - Genesis 5:3-5

Genesis 5:3-5 ESV 

When Adam had lived 130 years, he fathered a son in his own likeness, after his image, and named him Seth. The days of Adam after he fathered Seth were 800 years; and he had other sons and daughters. Thus all the days that Adam lived were 930 years, and he died.

Adam was created in the likeness of God. He then fathered his son Seth in his own likeness, which was different from the way he began life. He had fallen from his intimate relationship with God and had assumed a life further from God and a little closer to the life of a beast of the field. 

Seth means "compensation". He took the place of Abel who was killed by his brother Cain. 

Thus begins the genealogical tree to the birth of Noah.