Answer... 
Easy Answer: 66
But there is more...
39 in the Hebrew Scriptures
27 in the Christian Scriptures

Catholic Bibles have MORE books (called the Apocrypha) 

Why it matters? (Why do you think it matters?)
It doesn't really matter if you know the numbers. It matters that you know there is a variety of books that came together over thousands of years. Each book has its own history.  Some histories are connected to other religions. 

Now What?
Have you ever looked at the Table of Contents in your Bible?

Bonus - Five More Minutes

My favorite SUPER cheesy "Bible" songs

Old Testament Bop

New Testament Rock

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