From the liner notes

Samantha, a powerful member of the society of witches that has lived apart from (and disdained) humanity for many centuries, falls in love with a mortal, Darrin Stephens. Much to the disgust of most of her family, she vows to give up witchcraft and become an ordinary suburban housewife, raising a family (bearing Tabitha and Adam). Never able to give up her heritage completely, the friction between the matriarchal, moneyless society of her birth and the patriarchal, capitalist society of modern advertising drives the comedy over eight seasons and 256 episodes, from 1964 to 1971.