What is considered a block? What is not considered?

Question
Does it only count as a block if you are trying to block an attack hit or is it any attempt to block the ball coming over the net considered a block.   ie if a back row player hits the ball over the net, 1 2 or 3 hit and a player on the other team jumps up to block and only tips it back onto their own side.  is that a block or a first contact.

Answer
Hey Michael!
It's great to hear from you.  Welcome to www.allexperts.com.
There's an easy answer to your complex question:  What was the intent of the girl on defense?  Was she trying to block it? In your example of a back row player taking the ball over, yes, she was trying to block it, therefore, she her team gets three more hits.  
On the other hand, suppose she took a swing at the ball, whiffed on it, the ball is hovering over her head.  Well, her team only gets 2 more contacts, and she cannot make the next hit.  
So, it doesn't matter where the ball is coming from:  back row, front row, spiker, setter, or even the ball is bumped over.  What matters is, "What was the girl at the net trying to do?"  If she was trying to block it, then her team has 3 more hits.  
I hope that answers your question.  If not, please follow up.  
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