PARENTING GONE BAD – Is beating your child abuse or discipline?

Seeing all the tweets about how our parents raised us and while some are out rightly funny, others are thought-provoking and sad (A few at the bottom of the page). The question remains, is beating your child abuse, or is it discipline? Do these beatings have lasting effects? Are they necessary? Are there better ways to train the child that do not involve the whip?